Cardiovascular health, Immunity-infections, Pregnancy Flashcards

Question

encephalitis

Answer 1

Inflammation of the brain; fever, headache, nausea, and lethargy are common initial symptoms, followed in some cases by memory loss, seizures, brain damage, and death.

Answer 2

Persistent and relatively widespread in a given population.

Answer 3

The occurrence in a particular community or region of more than the expected number of cases of a particular disease.

Answer 4

A single-celled or multicelled organism that absorbs food from living or dead organic matter; examples include molds, mushrooms, and yeasts. Fungal diseases include yeast infections, athlete’s foot, and ringworm.

Answer 5

An intestinal disease caused by the protozoan Giardia lamblia.

Answer 6

A lymphocyte that helps activate other T cells and may help B cells produce antibodies.

Answer 7

Inflammation of the liver, which can be caused by infection, drugs, or toxins.

Answer 8

A family of viruses responsible for cold sores, mononucleosis, chicken pox, and the STI known as herpes; often causes latent infections.

Answer 9

A chemical responsible for the dilation and increased permeability of blood vessels in allergic reactions.

Answer 10

Mechanisms that defend the body against infection; specific defences against specific pathogens.

Answer 11

The period when bacteria or viruses are actively multiplying inside the body’s cells; usually a period without symptoms of illness.

Answer 12

Invasion of the body by a microorganism.

Answer 13

Infection of the respiratory tract by the influenza virus, which is highly infectious and adaptable; the form changes so easily that every year new strains arise, making treatment difficult; commonly known as the flu.

Answer 14

Increased bile pigment levels in the blood, characterized by yellowing of the skin and the whites of the eyes.

Answer 15

A lymphocyte that kills body cells that have been invaded by foreign organisms; also can kill cells that have turned cancerous.

Answer 16

A system of vessels and organs that picks up excess fluid, proteins, lipids, and other substances from the tissues; filters out pathogens and other waste products; and returns the cleansed fluid to the general circulation.

Answer 17

A white blood cell continuously made in lymphoid tissue as well as in bone marrow.

Answer 18

A large phagocytic (cell-eating) cell that devours foreign particles.

Answer 19

A severe, recurrent, mosquito-borne infection caused by the protozoan Plasmodium.

Answer 20

Lymphocytes generated during an initial infection that circulate in the body for years, “remembering” the specific antigens that caused the infection and quickly destroying them if they appear again.

Answer 21

Infection of the membranes covering the brain and spinal cord (meninges).

Answer 22

A small bacterium with an incomplete cell wall that may cause sore throats, ear infections, and pneumonia.

Answer 23

A type of white blood cell that engulfs foreign organisms and infected, damaged, or aged cells; particularly prevalent during the inflammatory response.

Answer 24

A disease epidemic that is unusually severe or widespread; often used to refer to worldwide epidemics affecting a large proportion of the population.

Answer 25

An organism that lives on or within a living host; the relationship benefits the parasite and harms the host.

Answer 26

A pathogen that causes intestinal and other infections; includes tapeworms, hookworms, pinworms, and flukes.

Answer 27

An organism that causes disease.

Answer 28

Inflammation of the lungs, typically caused by infection or exposure to chemical toxins or irritants.

Answer 29

A disease of the nervous system, sometimes crippling; vaccines now prevent most cases of polio.

Answer 30

Proteinaceous infectious particles thought to be responsible for a class of neurodegenerative diseases known as transmissible spongiform encephalopathies; Creutzfeldt-Jakob disease in humans and bovine spongiform encephalopathy (“mad cow disease”) are examples of prion diseases.

Answer 31

The stage of an infection, after incubation, during which initial symptoms begin to appear but the host does not feel ill; a highly contagious period.

Answer 32

A microscopic single-celled organism that often produces recurrent, cyclical attacks of disease.

Answer 33

A natural environment in which a pathogen typically lives.

Answer 34

A bacterium that can reproduce only inside living cells, transmitted by ticks, fleas, and lice; causes Rocky Mountain spotted fever and typhus.

Answer 35

Any of a genus (Staphylococcus) of spherical, clustered bacteria commonly found on the skin or in the nasal passages; staphylococcal species may enter the body and cause conditions such as boils, pneumonia, and toxic shock syndrome.

Answer 36

Any of a genus (Streptococcus) of spherical bacteria; streptococcal species can cause skin infections, strep throat, rheumatic fever, pneumonia, scarlet fever, and other diseases.

Answer 37

A lymphocyte that inhibits the growth of other lymphocytes.

Answer 38

An infection spread by the blood or lymphatic system to large portions of the body.

Answer 39

A lymphocyte that arises in bone marrow and matures in the thymus (thus its name).

Answer 40

Sudden onset of fever, aches, vomiting, and peeling rash, followed in some cases by shock and inflammation of multiple organs; often caused by a toxin produced by Staphylococcus aureus.

Answer 41

A poisonous substance produced by a microorganism.

Answer 42

A chronic bacterial infection that usually affects the lungs.

Answer 43

A preparation of killed or weakened microorganisms, inactivated toxins, or components of microorganisms that is administered to stimulate an immune response; a vaccine protects against future infection by the pathogen.

Answer 44

An insect, rodent, or other organism that carries and transmits a pathogen from one host to another.

Answer 45

A very small infectious agent composed of nucleic acid (DNA or RNA) surrounded by a protein coat; lacks an independent metabolism and reproduces only within a host cell.

Answer 46

pathogen, reservoir, portal of exit, means of transmission, portal of entry, and new host.

Answer 47

• The cycle begins with a pathogen, a disease-causing microorganism. Many illnesses are caused by toxins produced by the pathogen; others occur when the pathogen directly invades cells.

Answer 48

• The reservoir is the natural environment of the pathogen: a person, an animal, or an environmental component.

Answer 49

• The pathogen leaves the reservoir through a portal of exit, such as saliva, mucous membranes, or blood.

Answer 50

* Direct transmission passes the pathogen from the infected host to another person without an intermediary agent. Most respiratory infections are transmitted hand-to-hand. Other means of transmission include sexual contact or contact with blood. * Animals or insects serve as vectors, carrying the pathogen from one host to another, in indirect transmission. Pathogens also can be transmitted indirectly via contaminated objects or through air.

Answer 51

* The portal of entry through which a pathogen enters the body may be direct contact with or penetration of the skin, inhalation of particles, or ingestion of contaminated food or water. * Pathogens that enter the skin or mucous membranes can cause local tissue infection or may penetrate the lymphatic system or bloodstream. * Organisms that are transmitted via respiratory secretions may cause upper respiratory infections or pneumonia or may enter the bloodstream. * Foodborne and waterborne organisms enter the mouth and travel to the location that will best support their reproduction.

Answer 52

* After entering a new host, a pathogen is less likely to cause infection if the host has a strong immune system or resistance to the pathogen. * The number of pathogens introduced also is important. * If conditions are right, the pathogen will produce disease in the new host, which may become a reservoir from which a new chain of infection starts.

Answer 53

* Interruption of the chain through public health measures and individual action can prevent disease. * A pathogen’s reservoir can be isolated and destroyed. * Public sanitation practices can kill pathogens. * Transmission can be disrupted through hand washing and wearing of face masks. * Immunization or treatment of infected hosts can stop a pathogen from multiplying.

Answer 54

* The immune system is the body’s collective physical and chemical defenses against foreign organisms and pathogens * The immune system is our first line of defence

Answer 55

* Skin prevents microorganisms from entering the body * Membranes protect us when skin does not cover an area as the cells contained within the membrane are designed to prevent the passage of unwanted organisms and particles * Cilia are cells with hair-like protrusions that sweep foreign matter up

Answer 56

- Immunological defenders are white blood cells that are continuously being produced in the bone marrow: - Neutrophils travel in the bloodstream to areas of invasion attacking and ingesting pathogens - Macrophages are big eaters and devour pathogens and worn-out cells - Natural killer cells directly destroy virus-infected and cancerous cells - Dendritic cells reside in tissues, eat pathogens, activate lymphocytes - Lymphocytes travel in the bloodstream and lymphatic system; two types of cells

Answer 57

* The two kinds of lymphocytes are T cells and B cells. * The lymphocytes known as T cells are differentiated into helper T cells, killer T cells, and suppressor T cells. * B-cell lymphocytes produce antibodies. * Some T cells and B cells become memory cells that let the body respond rapidly to subsequent invasions by an agent.

Answer 58

* The immune system is built on the ability to distinguish foreign cells from the body’s own cells. * When the immune system goes awry, and the immune system cells attack the body itself, autoimmune diseases such as lupus and rheumatoid arthritis occur. * Cells display surface markers that identify them as “self” or “oneself” to lymphocytes. * The non-self markers that trigger the immune response are known as antigens. * When an antigen appears, antibodies lock onto it by a keylike mechanism specific to the antigen. The body’s resources are mobilized to destroy it and others like it. * Antibodies are already present in the body with complementary markers for millions of possible antigens.

Answer 59

* Histamine is a chemical responsible for the dilation and increased permeability of blood vessels in allergic reactions * This produces increased heat, swelling, and redness in the affected area * Pus is a collection of dead white blood cells and debris

Answer 60

* The immune system can develop two kinds of responses to invading pathogens: natural and acquired. Both responses occur each time the immune system is activated. * Neutrophils, macrophages, and natural killer cells are part of the natural response. They destroy the pathogen without any memory of past infections. * The acquired response of T cells and B cells changes after the first contact with the pathogen, and they develop a memory of the antigen. If the pathogen invades the body again, the T and B cells recognize the pathogen, and the response is much more potent.

Answer 61

The immune system has four phases: • First, dendritic cells arrive, consume foreign cells, and relay information to helper T cells, which rush to respond. • Helper T cells multiply rapidly and trigger production of killer T cells and B cells in the spleen and lymph nodes. Cytokines such as interleukins and interferons stimulate production of T cells, B cells, and antibodies. • Killer T cells destroy foreign cells and cells of the body that have been invaded and infected, in a process called the cell-mediated immune response. B cells produce antibody molecules that bind to antigen-bearing targets, thereby marking them for macrophages to consume, in a process called antibody-mediated immune response. They do not attack infected body cells. • When the invader is under control, suppressor T cells stop the immune response and restore balance. Dead cells are filtered and excreted.

Answer 62

* Immunity refers to mechanisms that defend the body against infection; specific defenses against specific pathogens * Acquired immunity is the body’s ability to mobilize the cellular memory of an attack by a pathogen to throw off subsequent attacks; acquired through vaccination and the normal immune response * Immunity occurs when lymphocytes are reserved as memory T cells and B cells. * Memory cells circulate in the blood, recognize the invader if it arrives again, and destroy it before it can cause illness. * The subsequent response to an invader takes much less time and is known as acquired immunity.

Answer 63

• During incubation, when pathogens are multiplying in the body, there may be no symptoms of the illness, but a person may be contagious. • Symptoms first appear in the prodromal period after incubation. • Many of the symptoms of an illness are due to the immune response rather than to the invading organism. • Cytokines may be responsible for fever. Cytokines travel to the brain and reset the body’s thermostat to a higher level to improve immune responses. -Cold symptoms are caused by the destruction of body cells by lymphocytes, and flu symptoms are caused by interferons. • Incubation is the period when bacteria or viruses are actively multiplying inside the body’s cells; usually a period without symptoms of illness • Many symptoms of an illness are actually due to the immune response of the body rather than to the actions or products of the invading organism

Answer 64

* Immunization is the process of “priming” the body with an antigen similar to the pathogenic organism but not as dangerous. This vaccine allows the immune system to develop antibodies that will destroy the more serious antigens, should they be introduced into the body. * Vaccines are made today by weakening (or attenuating) the actual organisms (rubella, mumps, measles) or by using pathogens (e.g., influenza) that were first killed in the laboratory but that still stimulate antibody production. * Vaccines confer active immunity. The vaccinated person creates his or her own antibodies. * In some cases, people can be injected with antibodies themselves, produced by other human beings or by animals. * The phenomenon is called passive immunity. * Gamma globulin, made from the plasma of many people and containing all their antibodies, is an example of this phenomenon. It is used to provide rapid, but temporary, immunity. * The number of illnesses and deaths from vaccine-preventable diseases are at near record low levels in Canada, while more than 4 million people -- most of them infants and children in developing countries – die each year from vaccine-preventable diseases. * While side effects from immunizations usually are mild, an allergic reaction may occur in less than 1 in 1 million doses. Any risk from vaccines must be balanced against the risk posed by the disease they prevent.

Answer 65

* Allergies are a disorder caused by the body’s exaggerated response to foreign chemicals and proteins * Allergies result from a hypersensitive and overactive immune system * Allergies result from the response of a hypersensitive and overactive immune system to a harmless substance, such as pollen or animal dander. Symptoms result from the immune response rather than from the substances that provoke the response.

Answer 66

• Substances that provoke allergies are known as allergens. The following are common allergens. • Weeds, grasses, and trees produce common pollen allergens. • Animal allergies result from animal dander (dead skin flakes), urine, or a protein found in saliva. • Droppings of microscopic dust mites and cockroaches can trigger allergies. • Molds and mildew produce small spores that can trigger symptoms. • The most common food allergens include peanuts, tree nuts, fish, and shellfish. • The venom of stings from yellow jackets, honeybees, hornets, paper wasps, and fire ants can cause allergic reactions in some people. Certain medications, plants such as poison oak, metals such as nickel, latex, and compounds found in cosmetics also may cause allergic reactions.

Answer 67

• Most allergic responses are due to the production of an antibody known as immunoglobulin E (IgE). • The first exposure to the allergen may cause little response, but it sensitizes the immune system, causing the production of allergen-specific IgE, which binds to mast cells. • During a later exposure to the allergen, the allergen binds itself to IgE, causing mast cells to release large amounts of histamine and other compounds into surrounding cells. • Histamine increases the inflammatory response and stimulates mucus production. Symptoms depend on which body part is affected. • In the nose, histamine may cause congestion and sneezing; in the skin, redness, swelling, and itching; in the intestines, bloating and cramping; and in the lungs, coughing, wheezing, and shortness of breath. • In some people, an allergen can trigger an asthma attack, which can occur within minutes of exposure. Inflammatory reactions may take hours or days to develop and persist for several days.

Answer 68

Anaphylaxis, the most serious and possibly life-threatening reaction, results from a release of histamine throughout the body. Swelling of the throat, extremely low blood pressure, fainting, heart arrhythmia, and seizures can occur. Immediate injection of epinephrine is required.

Answer 69

* Avoidance (avoid or minimize exposure to allergens) * Medication (over-the-counter antihistamines help to control symptoms; prescription corticosteroids markedly reduce symptoms) * Immunotherapy (allergy shots desensitize a person to a particular allergen)

Answer 70

* Worldwide, infectious diseases are responsible for more than 25% (or about 15 million) deaths each year * Pathogens include bacteria, viruses, fungi, protozoa, parasitic worms, and prions

Answer 71

• Bacteria are microscopic single-celled organisms • Most abundant living things on Earth • Can be helpful (digest nutrients in the colon) or harmful (invade cells or produce damaging toxins)

Answer 72

• They are classified according to their shape: bacilli (rod shaped), cocci (spherical), spirochete (spiral shaped) and vibrios (comma shaped). • Sexual activity can introduce bacteria into the reproductive tract. • If bacteria enter areas of the body that are bacteria-free, such as the blood stream, tissues, and organs, infection may result. The immune system provides surveillance against such invaders. • Inflammation of the lungs, pneumonia, may be caused by infection with bacteria, viruses, or fungi, or by contact with chemical toxins or irritants. • Infection of the membranes covering the brain and spinal cord, meningitis, is usually mild and goes away on its own. Bacterial meningitis can be life threatening and requires immediate treatment with antibiotics. • The streptococcus bacterium causes strep throat, which is spread by contact with an infected person via coughing and sneezing. If untreated, strep throat can develop into rheumatic fever. • Toxic shock syndrome is caused by a staphylococcus bacterium producing a deadly toxin that causes life-threatening low blood pressure, high fever, a peeling skin rash, and inflammation of several organs. The incidence of toxic shock dropped dramatically after a particular type of tampon was removed from the market. • Tuberculosis is a chronic bacterial infection (Mycobacterium tuberculosis) that usually affects the lungs and is spread via the respiratory route. Many strains of the disease respond to antibiotics, but failure to complete the 6-month to 12-month treatment can lead to relapse and the development of antibiotic-resistant bacteria. • The emergence of tuberculosis with extensive resistance to second-line drugs – the drugs primarily used against bacterial infections – is of concern. • Lyme disease is spread by the bite of a tick that is infected with the bacterium Borrelia burgdorferi. It accounts for more than 95% of all reported vector-borne illness in Canada. Without treatment for Lyme disease, a recurring arthritis can develop, and fetal damage or death can occur at any stage in pregnancy. • As many as 90% of all ulcers are caused by infection with Helicobacter pylori. Antibiotics often cure the infection and the ulcers -Other bacterial infections include tetanus, caused by Clostridium tetani; pertussis (whooping cough), caused by Bordetella pertussis; and urinary tract infections, caused by Escherichia coli.

Answer 73

• Antibiotics are both naturally occurring and synthetically created substances; they can kill bacteria. • Most antibiotics interrupt the production of new bacteria by disrupting some part of their reproductive cycle or by causing faulty parts of new bacteria to be made. • Penicillins inhibit formation of bacterial cell walls when bacteria divide into new cells. • Other antibiotics inhibit production of certain necessary proteins by the bacteria; others interfere with the reading of DNA during the process of reproduction. • When antibiotics are misused or overused, the pathogens they are designed to treat can become resistant to their effects. • Antibiotic-resistant strains of many common bacteria have developed, including strains of gonorrhea and salmonellosis (a foodborne illness). • One strain of tuberculosis is resistant to seven different antibiotics. • Antibiotic resistance is a major factor contributing to the recent rise in problematic infectious diseases. • Resistance is promoted when people fail to take the full course of an antibiotic or when they inappropriately take antibiotics for viral infections. Another source of resistance is in the use of antibiotics in agriculture. At least four species of antibiotic-resistant bacteria are documented to have transmitted from food animals to humans.

Answer 74

• Don’t take an antibiotic every time you get sick • Use antibiotics as directed and finish the full course of medication • Never take an antibiotic without a prescription

Answer 75

* Viruses are very small infectious agents composed of nucleic acid surrounded by a protein coat * Viruses lack an independent metabolism and reproduce only within a host cell * Lack all enzymes essential to energy production and protein synthesis in normal animal cells * Viruses are parasites * Cannot grow or reproduce themselves * Take what they need for growth and reproduction from the cells they invade (parasites) * Cause illnesses known as contagious diseases * Viruses cannot grow or reproduce by themselves. They are parasites, using host cells to manufacture more viruses like themselves. Illnesses caused by viruses are the most common forms of contagious disease. Different viruses affect different kinds of cells, and the seriousness of the disease depends on the type of cell affected. * The common cold, lasting only 4 to 7 days, may be caused by any of more than 200 different viruses that attack the lining of the nasal passages. * Rhinoviruses and coronaviruses cause most colds and are transmitted mainly by hand-to-hand contact. Therefore, washing your hands frequently is the best prevention. * Treatment generally uses over-the-counter medications. * Determining whether symptoms are caused by a virus, a bacterium, or an allergy is important for selecting the appropriate treatment.

Answer 76

May be caused by any of more than 200 different viruses that attack lining of nasal passages Almost always transmitted by hand-to-hand contact Wash your hands frequently

Answer 77

* Infection of the respiratory tract * Fever, extreme fatigue * Life-threatening complications such as pneumonia can develop * Highly contagious * Gastrointestinal illness, sometimes called the “stomach flu,” is caused by organisms other than the influenza virus. * Influenza is more serious than the common cold, and symptoms include fever and extreme fatigue. Most people recover from the flu in a couple of days, but some develop potentially life-threatening complications, such as pneumonia. * Getting an annual vaccination is the best way to prevent the flu. * Those most at risk from complications or death from influenza are children 6 to 23 months old, people 65 years or age and older, anyone 2 to 64 years old with long-term health conditions, anyone with a weakened immune system, women who will be pregnant during the flu season, residents of nursing homes and long-term care facilities, persons 6 months to 18 years old on long-term aspirin treatment, healthcare workers with direct patient contact, and household contacts of persons at high risk. * Influenza is an infection of the upper respiratory tract caused by the influenza virus. * Gastrointestinal illness, sometimes called the “stomach flu,” is caused by organisms other than the influenza virus. * Influenza is more serious than the common cold, and symptoms include fever and extreme fatigue. Most people recover from the flu in a couple of days, but some develop potentially life-threatening complications, such as pneumonia. * Getting an annual vaccination is the best way to prevent the flu. * Those most at risk from complications or death from influenza are children 6 to 23 months old, people 65 years or age and older, anyone 2 to 64 years old with long-term health conditions, anyone with a weakened immune system, women who will be pregnant during the flu season, residents of nursing homes and long-term care facilities, persons 6 months to 18 years old on long-term aspirin treatment, healthcare workers with direct patient contact, and household contacts of persons at high risk.

Answer 78

• Effective vaccines have reduced the incidence of childhood viral illnesses. • Measles and rubella (German measles) are characterized by rash and fever and occasionally can cause more severe illness, including liver or brain infection or pneumonia. • If rubella infects a pregnant woman, it can be transmitted to the fetus, causing miscarriage, stillbirth, and severe birth defects. -Mumps generally causes swelling of the salivary glands. This virus also can cause meningitis and inflammation of the testes in males.

Answer 79

* With infection by the herpesvirus, the person never is free of the virus, with episodes of activity and dormancy recurring. This virus can be dangerous for people with weakened immune systems, as in the case with HIV infection. * Chicken pox and shingles are caused by the Varicella-zoster virus. Chicken pox is highly contagious in childhood and may reactivate and cause shingles many years later. A new vaccine for people age 60 and older, Zostavax, reduced the risk of shingles in older adults up to 64%. * Herpes simplex virus (HSV) types 1 and 2 cause cold sores and the STI herpes. Small painful sores occur around the mouth or genitals, the site of first contact with the virus. After initial infection, HSV becomes latent and can reactivate repeatedly over time. Medications are available to prevent recurrences of genital herpes. * Epstein-Barr virus (EBV) causes infectious mononucleosis, which is characterized by fever, sore throat, swollen lymph nodes, and fatigue. The disease can reactivate throughout life, but generally does not cause further symptoms, although for those with HIV infection, EBV is associated with the development of cancers of the lymph system. * Cytomegalovirus, which infects the lungs, brain, colon, and eyes, and human herpesvirus 8, which is linked to Kaposi’s sarcoma, can produce severe infections in people with suppressed immune systems. * HSV type 1is a possible cause of viral encephalitis, which causes inflammation of brain tissue resulting from a viral infection. Other possible causes include HIV or severe mosquito-borne viruses. Severe cases are characterized by memory loss, delirium, reduced speech function, seizures, and possibly brain damage or death. * Viral hepatitis describes several different infections that cause inflammation of the liver. * Hepatitis A virus (HAV) is the mildest form of the disease and usually is transmitted by an infected person or food or water contaminated by sewage. * Hepatitis B virus (HBV) usually is transmitted sexually. * Hepatitis C virus (HCV) is most often passed through direct contact with infected blood via injection, drug use, or, before screening tests were instituted, blood transfusion. * HBV and HCV can be passed from a pregnant woman to her child. * Although there are vaccines for hepatitis A and B, there are new cases reported each year in Canada. * Most people recover from hepatitis A, but about 5% to 10% of people infected with HBV and 85% to 90% of those infected with HCV become chronic carriers of the disease. * While some chronic carriers remain asymptomatic, others develop chronic liver disease, cirrhosis, or liver cancer. * HCV is the most common reason for liver transplants in Canada and is thought to be a factor in the 70% increase in liver cancer rates since the 1970s. Testing for HCV is recommended for people at risk. * Poliomyelitis is a viral disease that affects the nervous system and can cause irreversible paralysis and death. North and South America are considered free of the disease because of a vaccine. * Rabies is a potentially fatal infection of the central nervous system that is most often transmitted through an animal bite. Although rabies is rare in Canada because of widespread vaccination of domestic animals and the development of a highly effective vaccine regimen, most recent cases have been traced to bats. * Warts are noncancerous skin tumours caused by the human papillomavirus (HPV). There are more than 100 types of HPV that can cause a variety of warts, including warts on hands, plantar warts on the feet, and genital warts around the genitalia.

Answer 80

* Antiviral drugs work by interfering with some part of the viral life cycle * Antivirals are currently available to fight infections caused by HIV, influenza, herpes simplex, varicella- zoster, HBV, and HVC

Answer 81

* A fungus is an organism that absorbs food from organic matter * Fungi are primitive plants that can be multicellular or unicellular. * Only about 50 of several thousand fungi cause human diseases, which involve primarily the skin, mucous membranes, and lungs. * Candida albicans is a common fungus. When it grows excessively, it can cause infections, especially in the vagina and in infants’ mouths (thrush). Infection can be mild or progress to severe inflammation of mucous membranes. * Athlete’s foot, jock itch, and ringworm all are fungal infections. * Severe, life-threatening systemic diseases that are fungal in origin are histoplasmosis and coccidioidomycosis (“valley fever”). * Fungal infections can be especially deadly in those with an impaired immune system.

Answer 82

* Protozoa, which are microscopic, single-celled organisms, cause diseases such as malaria, Giardiasis, Trichomoniasis, African sleeping sickness, and amoebic dysentery. * Malaria is caused by protozoa injected into the bloodstream via a mosquito bite. Although rare in Canada, malaria is a major killer worldwide. Drugs are available to prevent and treat the disease. * Trichomoniasis is a relatively mild, treatable vaginal infection that may increase the risk of HIV transmission. * Giardiasis, one of the most common waterborne diseases in Canada, is contracted by the drinking of untreated water. * Millions of people in developing countries have protozoal infections

Answer 83

* Parasitic worms are the largest organisms that enter the body and cause infection. * Worms, including such intestinal parasites as the tapeworm and hookworm, cause a variety of mild infections. * Pinworm is the most common infection in Canada and affects primarily young children. * Some smaller worms, such as flukes, infect the liver or lungs and can be deadly in large enough numbers. * Worm infections generally originate in contaminated food or drink. Most are relatively mild and can be controlled by careful attention to hygiene. * They are the largest organisms that can enter the body to cause infection

Answer 84

• Prions, or “proteinaceous infectious particles,” form deposits in the brain. • Foetal degenerative disorders of the central nervous system have been linked to prions • Several fatal degenerative diseases have been linked with prions, which appear to lack DNA or RNA and consist of only protein. • Prions are associated with a class of diseases known as transmissible spongiform encephalopathies (TSEs). • Symptoms of TSEs include loss of coordination, weakness, dementia, and death. • Known prion diseases include Creutzfeldt-Jakob (CJD) disease in humans, bovine spongiform encephalopathy (“mad cow disease”) in cattle, and scrapie in sheep. • Their presence in the body does not trigger the immune response. • They are like sponge holes in the brain -Some prion diseases are inherited or are the result of spontaneous genetic mutations, while others are the result of the eating of infected tissue or exposure to prions during medical procedures such as transplants.

Answer 85

Infections whose incidence in humans has increased or threatens to increase in the near future West Nile virus Severe acute respiratory syndrome (SARS) Rotavirus Escherichia Coli o157:H7 Hantavirus Ebola

Answer 86

Key Facts: • Ebola virus disease (EVD), formerly known as Ebola haemorrhagic fever, is a rare but severe, often fatal illness in humans. • The virus is transmitted to people from wild animals and spreads in the human population through human-to-human transmission. • The average EVD case fatality rate is around 50%. Case fatality rates have varied from 25% to 90% in past outbreaks. • Community engagement is key to successfully controlling outbreaks. • Good outbreak control relies on applying a package of interventions, namely case management, infection prevention and control practices, surveillance and contact tracing, a good laboratory service, safe and dignified burials and social mobilisation. • Vaccines to protect against Ebola have been developed and have been used to help control the spread of Ebola outbreaks in Guinea and in the Democratic Republic of the Congo (DRC). • Early supportive care with rehydration, symptomatic treatment improves survival. Two monoclonal antibodies (Inmazeb and Ebanga) were approved for the treatment of Zaire ebolavirus (Ebolavirus) infection in adults and children by the US Food and Drug Administration in late 2020. • Pregnant and breastfeeding women with Ebola should be offered early supportive care. Likewise vaccine prevention and experimental treatment should be offered under the same conditions as for non-pregnant population.

Answer 87

* Emerging infectious diseases include both known diseases that have experienced resurgence, such as tuberculosis and cholera, and diseases that were previously unknown or confined to specific areas. Emerging infections of concern include avian influenza, mad cow disease, West Nile Virus, severe acute respiratory syndrome (SARS), Influenza A (H5N1), Rotavirus, E. coli 0157:47, hantavirus, new variant CJD, Ebola, and infections caused by bioterrorism agents. Contributing factors behind the increase in infectious diseases include the following: * New or increasing drug resistance has been found in organisms that cause malaria, tuberculosis, gonorrhea, influenza, AIDS, and pneumococcal and staphylococcal infections. * Poverty, population growth, urbanization, overcrowding, and migration contribute to the spread of infectious diseases. * Inadequacies in the public health infrastructure can cause contamination of the water supply. * Environmental changes alter the distribution of disease vectors and bring people in contact with new pathogens. A shift in rainfall caused by global warming allows mosquito-borne diseases such as malaria and dengue fever to spread from the tropics into temperate zones. Natural disasters such as the 2004 tsunami also disrupt the public health infrastructure. * Travel and commerce open the world to infectious agents. * Mass food production and distribution increase the likelihood that a chance contamination can lead to mass illness. * Changes in human behaviour affect the spread of infectious diseases. * Changes in human behaviour affect the spread of infectious diseases. * The use of injectable drugs rapidly transmits HIV infection and hepatitis. * Changes in sexual behaviour have led to a proliferation of new and old STIs. * The use of day-care facilities for children has led to increases in the incidence of several infections that cause diarrhea. * The deliberate release of deadly infectious agents, known as bioterrorism, is an ongoing concern. * Cancer is an example of the body’s suffering an attack by its own cells, which multiply uncontrollably. * In a healthy person, the immune system can destroy newly cancerous cells. * If the body’s immune system breaks down and cannot recognize the rapid growth as abnormal, it will not attack the cells and will not fight. * If the body confuses its own cells with foreign antigens, it will seek and destroy its own cells, as in rheumatoid arthritis and systemic lupus erythematosus.

Answer 88

* We can prevent infection by pathogens by removing them from the environment or removing the conditions that increase their ability to reach people. * Public health measures such as sanitation and hygiene are critical to this process. * Proper food inspection and preparation is essential to preventing illness caused by foodborne pathogens. * Adequate nutrition, exercise, rest, and moderation in lifestyle allow the body to keep its immune system at its best. * People are more vulnerable to disease at certain times in life: as newborns, in old age, and at times of high stress. * Getting necessary immunizations is one of the best preventive measures. * See the following link for the updated Canadian Immunization Guide: * https://www.canada.ca/en/public-health/services/canadian-immunization-guide.html * The higher the stress level, the lower the number of helper T cells a person has. Developing ways of coping with stress is essential to maintaining good health. * A healthy lifestyle is the best defensc against disease.

Answer 89

A process in which amniotic fluid is removed and analyzed to detect possible birth defects.

Answer 90

A membranous pouch enclosing and protecting the fetus, containing amniotic fluid.

Answer 91

A formalized system for assessing a newborn’s need for medical assistance.

Answer 92

The introduction of semen into the vagina by artificial | means, usually by syringe.

Answer 93

A stage of development, days 6-14, when the cell cluster becomes the embryo and placenta.

Answer 94

A surgical incision through the abdominal wall and uterus, performed to extract a fetus.

Answer 95

Surgical removal of a tiny section of chorionic villi to be | analyzed for genetic defects.

Answer 96

Asexual reproduction in which offspring are genetically identical to one parent.

Answer 97

A yellowish fluid secreted by the mammary glands around the time of childbirth until milk comes in, about the third day.

Answer 98

A physical defect existing at the time of birth, either inherited or caused during gestation.

Answer 99

Shortening of the muscles in the uterine wall, which causes effacement and dilation of the cervix and assists in expelling the fetus.

Answer 100

A severe, potentially life-threatening form of preeclampsia, characterized by seizures.

Answer 101

A pregnancy in which the embryo develops outside of the uterus, usually in the fallopian tube.

Answer 102

The use of an external or internal electronic monitor during labour to measure uterine contractions and fetal heart rate.

Answer 103

The stage of development between blastocyst and fetus; about weeks 2-8.

Answer 104

An incision made to widen the vaginal opening to facilitate childbirth and prevent uncontrolled tearing during delivery.

Answer 105

The initiation of biological reproduction: the union of the nucleus of an egg cell with the nucleus of a sperm cell.

Answer 106

The egg after penetration by a sperm; a zygote.

Answer 107

A combination of birth defects including physical, social, cognitive, and emotional problems caused by excessive alcohol consumption by the mother during pregnancy.

Answer 108

The developmental stage of a human from the ninth week after conception to the moment of birth.

Answer 109

Twins who develop from separate fertilized eggs; not genetically identical.

Answer 110

Surgically introducing eggs and sperm into the | fallopian tube before fertilization.

Answer 111

A package of chemical instructions, or hereditary material, that defines an individual’s unique traits.

Answer 112

A form of diabetes that occurs during pregnancy.

Answer 113

A hormone produced by the fertilized egg that can be detected in the urine or blood of the mother within a few weeks of conception.

Answer 114

Twins who develop from the division of a single zygote; genetically identical.

Answer 115

The death of a child less than 1 year of age.

Answer 116

The inability to conceive after trying for a year or more.

Answer 117

Combining egg and sperm outside of the body and inserting the fertilized egg into the uterus.

Answer 118

The act or process of giving birth to a child, expelling it with the placenta from the mother’s body by means of uterine contractions.

Answer 119

The production of milk.

Answer 120

A process in which the uterus sinks down because the baby’s head settles into the pelvic area.

Answer 121

Weighing less than 2.5 kilograms (5.5 pounds) at birth, often the result of prematurity.

Answer 122

The organ through which the fetus receives nourishment and empties waste via the mother’s circulatory system; after birth, the placenta is expelled from the uterus.

Answer 123

A complication of pregnancy in which the placenta covers the cervical opening, preventing the mother from delivering the baby vaginally.

Answer 124

A complication of pregnancy in which a normally implanted placenta prematurely separates from the uterine wall.

Answer 125

An emotional low that may be experienced by the mother after childbirth.

Answer 126

The period of about 3 months after delivering a baby.

Answer 127

Health care in preparation for pregnancy.

Answer 128

A condition of pregnancy characterized by high blood pressure, edema, and protein in the urine

Answer 129

Born before the 37th week of pregnancy.

Answer 130

A measurement of four hormones, used to assess the risk of fetal abnormalities.

Answer 131

A protein found in blood; Rh incompatibility between a mother and fetus can jeopardize the fetus’s health.

Answer 132

The practice of allowing the mother and baby to remain together in the hospital or birth center after delivery.

Answer 133

The visual image of the fetus produced by ultrasonography.

Answer 134

The sudden death of an apparently healthy infant during sleep.

Answer 135

An agent or influence that causes physical defects in a developing fetus.

Answer 136

The last part of the first stage of labour, during which the cervix becomes fully dilated; characterized by intense and frequent contractions.

Answer 137

One of the three 3-month periods of pregnancy.

Answer 138

The use of high-frequency sound waves to view the fetus in the uterus; also known as ultrasound.

Answer 139

The cord connecting the placenta and fetus, through which nutrients pass.

Answer 140

Surgically introducing a fertilized egg into the fallopian tube

Answer 141

* Preparation for parenthood begins with consideration of your own suitability and readiness to be a parent. Issues to be considered include the following: * Health and age * Teenagers and mothers over 35 have special health risks. * Some physical conditions, such as overweight, diabetes, and high blood pressure, require ongoing attention during pregnancy. * Emotional preparedness * Parents must be strong and stable enough to handle the responsibility that comes with caring for a child. * Financial circumstances * Prepared to spend about $10,000 per year per child * Relationships * New parents should have a strong network of support, be committed to parenthood and agree on matters of child care and other day-to-day responsibilities * Future plans * Will having a child cause you to postpone or cancel career or educational plans? The average cost of child care ranges from approximately $25 to $100 per day depending on the type of child care services, however lower rates are often available for those in need of financial assistance. * Attitude and aptitude * Both parents should be devoted to raising their child. There are many good sources of information for first time parents including: physicians, pediatrician, classes on labour, delivery, breastfeeding, and basic child care

Answer 142

* Preconception care can include assessment of health risks, promotion of healthy behaviours, and treatments needed to reduce risks. * Preexisting conditions * Diabetes, epilepsy, asthma, high blood pressure, and anemia should be treated and monitored throughout pregnancy. * Medications * You may need to change or stop takin certain drugs and supplements. * Prior pregnancies * Problems such as miscarriage, premature birth, or delivery complications should be investigated * Age * The mother’s age can increase the possibility of special health problems of infertility, of pregnancy, and of genetic or chromosomal disorders. * Tobacco, alcohol, and caffeine use * These substances can harm the developing fetus. * Infections * Consider whether you are up to date on immunizations, such as against hepatitis B, rubella (German measles) and varicella (chicken pox). You should also be tested for sexually transmitted diseases and tuberculosis. * HIV * If you are at risk for HIV infection, you should be tested. This includes your partner as well. * Diet * Nutritional counseling can help you create a healthy eating plan both before conception and during pregnancy. It is recommended that all women of childbearing age take extra folic acid to reduce the risk of neural tube defects in the fetus. * Multiple births * If multiple births run in a woman’s family it will increase the likelihood of a multiple birth. Multiple births are also increased in mothers older than 40 or using certain reproductive technologies to achieve pregnancy. * Genetic disease * Both partners should examine family histories for genetic diseases and get counseling as needed.

Answer 143

• Conception involves the fertilization of a woman’s egg by a man’s sperm. • Each month, a woman’s ovaries release a mature egg from its follicle. • Over the course of 3 to 4 days, the egg travels through the fallopian tube (oviduct) to the uterus. • The uterine lining (endometrium) has thickened in preparation for implantation of a fertilized egg (zygote). • If the egg is not fertilized, it disintegrates after about 24 hours and is expelled during the menstrual period. • Millions of sperm cells are released with each ejaculation. However, only a small percentage journey through the vagina and uterus and up the fallopian tubes. • The sperm that make the journey into the fallopian tube deposit enzymes that soften the outer surface of the egg. When enough of the substance is present, a break occurs in the surface, and one sperm will enter, fertilizing the egg. Thereafter no other sperm will be able to enter the egg. • The egg and sperm each carry 23 chromosomes, each of which contains many genes. Together they create the combination for a new human being. • The zygote immediately begins to undergo cell division that starts the growth process. • Fraternal twins come from two fertilized eggs; identical twins come from one fertilized egg that divides into two cells that develop separately. a. The most serious complication of multiple births is preterm delivery.

Answer 144

Fraternal twins • Twins who develop from separate fertilized eggs; not genetically identical Identical twins • Twins who develop from the division of a single zygote; genetically identical

Answer 145

* Of all Canadian couples (15%) are unable to have the children they want and may seek treatment for infertility. * The inability to conceive after trying for a year or more * Affects approximately 15% of the reproductive-age population of Canada * 40% of cases are found in women * 20% of cases are found in men * In 30% of infertile couples, both partners have problems * 10% of cases, the cause is unknown

Answer 146

* Anatomical abnormalities (10%) * Unexplained infertility (10%) implies that a cause for the infertility has not been found after completing all relevant investigations * Blocked fallopian tubes are most commonly the result of pelvic inflammatory disease (PID), a serious complication of several sexually transmitted infections such as chlamydia or gonorrhea * Endometriosis, a condition in which uterine tissue grows outside of the uterus, can reduce fertility * Age, exposure to toxic chemicals or radiation, and cigarette smoking can reduce fertility as well * Blockage of fallopian tubes (40%) or failure to ovulate (40%) are common causes observed in women. * Blockage of fallopian tubes can be caused by pelvic inflammatory disease, prior surgery, or endometriosis. * As a woman ages, fertility naturally begins to decline—the main reason for ovulation failure. Exposure to toxic chemicals and cigarette smoking also appears to reduce fertility.

Answer 147

``` • Accounts for about 20% of infertile couples • Four main categories • Hypothalamic pituitary disease or congenital disorders • Testicular disease • Disorders of sperm transport • Unexplained • Acquired disorders of the testes • Drug use • Radiation • Infection • Environmental toxins • Hyperthermia Male Infertility • Smoking ```

Answer 148

• Most treatments for infertility are expensive, are emotionally draining, and may become all-consuming for the couple involved. Surgery can repair oviducts, clear up endometriosis, and correct anatomical problems in both men and women. Fertility drugs can help women ovulate, although may cause multiple births. If these conventional treatments don’t work, couples can turn to assisted reproductive technology (ART). • Male infertility sometimes can be overcome by collecting and concentrating the man’s sperm and introducing it by syringe into a woman’s vagina or uterus, a procedure known as artificial insemination. The success rate is about 60%. • Three related techniques for overcoming infertility involve removing mature eggs from a woman’s ovary. • With in vitro fertilization (IVF), the harvested eggs are mixed with sperm in a laboratory dish. If eggs are fertilized, one or more or the resulting embryos are inserted into the woman’s uterus. IVF is often used by women with blocked oviducts. • In gamete intrafallopian transfer (GIFT), eggs and sperm are surgically placed into the fallopian tubes before fertilization. • In zygote intrafallopian transfer (ZIFT), eggs are fertilized outside the woman’s body and surgically introduced into the oviducts after they begin to divide. • IVF, GIFT, and ZIFT have success rates that vary from 27% to 51%, they cost $8000 to $12,000 per procedure, and they may require five or more cycles to produce one live birth. Surrogate motherhood involves a contract between an infertile couple and a fertile woman who agrees to carry a fetus. The surrogate mother agrees to be artificially inseminated by the father’s sperm or undergo IVF with the couple’s embryo, to carry the baby to term.

Answer 149

* Infertility sometimes leads to a feeling of loss of control over one’s life. Couples may need to limit the amount of treatment they are willing to undergo and may mourn the loss of children they will never have. It helps to make specific decisions about the future, whether that might involve adoption or accepting childlessness. * Feelings of having lost control over a major area of life * May lose perspective on the rest of their lives as focus grows on reasons for infertility and on treatment * Support groups are available

Answer 150

* Pregnancy tests detect the presence of human chorionic gonadotropin, a hormone produced by the implanted fertilized egg. * Tests are designed to detect human chorionic gonadotropin (HCG) * Can be used two weeks after fertilization * Home pregnancy tests must be administered according to instructions

Answer 151

* Pregnancy is usually viewed in terms of 13-week trimesters, based on fetal development. A woman’s body changes from the moment of conception and continues to change throughout her pregnancy. * A trimester is one of three, three-month periods of pregnancy * Each trimester is about 13 weeks * First trimester sees few physical changes, second trimester is peaceful, third trimester is most difficult

Answer 152

* Early signs and symptoms include: * Missed menstrual period; slight bleeding, which may be mistaken for a menstrual period; nausea; breast tenderness; increased urination; and sleepiness, fatigue, and emotional upset. * A softening of the uterus, called Hegar’s sign, and other changes to the cervix and uterus. * Changes in the woman’s body begin immediately but are obvious after the first trimester. * By the fourth month, the uterus is large enough to make the abdomen protrude, and by the seventh or eighth month, it protrudes up into the rib cage. * The breasts enlarge early and are sensitive by the eighth week, and the areola darken and broaden. * During pregnancy, the muscles and ligaments attached to the pelvic bones loosen and spread; the circulatory system becomes more efficient to accommodate a 50% increase in blood volume; lungs increase in efficiency and inhale up to 40% more air; and kidneys become highly efficient, removing waste products from fetal circulation. * Weight gain naturally occurs, and most women gain an average of 27.5 pounds. Good nutrition is critical during pregnancy. * About 60% of weight gain is due to the development of the baby, and the rest accumulates over the woman’s body as fluid and fat. * Many women also experience small breaks in the elastic fibers of the lower layer of skin, producing stretch marks and increased pigmentation.

Answer 153

* Changes and complications in later pregnancy include: * Backache, fluid retention, leg cramps, heartburn, or constipation. * Increased needs placed on moms lungs, heart, kidney * Preliminary contractions, usually short, irregular, and painless. * Lightening during the ninth month, when the baby settles into the pelvic cavity.

Answer 154

* Emotional responses to hormonal changes can cause unpredictable emotions in a woman. Certain emotional responses are typical throughout pregnancy. * Fears about miscarriage or about the health of the baby may dominate the first trimester. * Diminished delight over pregnancy is often part of the second trimester. A woman may worry that her increasing size makes her unattractive; her partner should reassure her that this is not so. * A woman may experience depression during the third trimester because of physical awkwardness and feelings of being sexually unattractive. Excitement and anticipation are also common feelings during this time.

Answer 155

* Fetal development follows a fairly predictable pattern. * 1. First trimester * a. During the first 4 days, the fertilized egg divides, then multiplies to 32 to 128 cells and travels to the uterus, where it is called a blastocyst. * b. On about the sixth or seventh day, it attaches to the upper curve of the uterine wall, drawing nourishment from the uterine lining (endometrium). * c. The blastocyst becomes an embryo by about the end of the second week, and cells begin to differentiate into three layers: inner body parts (digestive and respiratory systems); skin, hair, and nervous tissue; and muscle, bone, blood, kidneys, and sex gland. * d. The outermost shell of cells becomes the placenta, umbilical cord, and amniotic sac. The chorionic villi, a network of blood vessels, form the placenta, which brings oxygen and nutrients to the fetus and removes waste products. * e. All major body structures are formed between the second and ninth weeks of gestation. The heart begins to beat, and the liver starts producing blood cells. * f. By the end of the second month, the brain sends out impulses that coordinate other organs, and the embryo is considered a fetus. * g. At the end of the third month, the fetus is about 2.5 cm long and weighs less than 30 grams.

Answer 156

* During the second trimester, the fetus grows to about 35 cm and 680 grams. * a. All body systems operate, and the fetal heartbeat can be heard with a stethoscope. * b. The mother begins to feel fetal movement during the fourth or fifth month. * c. A fetus born at the end of the second trimester can survive, but the odds are against it.

Answer 157

* During the third trimester, the fetus gains most of its birth weight. * Fetus gains protective fat layers, respitory and digestive organs develop. * a. About 85% of the calcium and iron the mother consumes goes into the fetal bloodstream. * b. During this time, the fetus gains protective fat layers, respiratory and digestive organs develop more fully, and the mother’s blood brings immunities to the fetus.

Answer 158

* Prenatal testing can develop information about the health and sex of the fetus. * Sonograms, also called ultrasound, show position, size, and gestational age of the fetus, as well as certain anatomical problems. They can sometimes detect the sex of the fetus. About 3% of babies are born with a major birth defect. * Amniocentesis, the removal of fluid from the uterus with a long, thin needle, can reveal the presence of Down syndrome, Tay-Sachs disease, and other conditions caused by chromosomal or genetic abnormalities. It is usually performed at 15 to 18 weeks of gestation, although earlier amniocentesis is becoming available at some centers. Most amniocenteses are performed on mothers over age 35 or when the fetus is at risk for a certain defect. * Chorionic villus sampling (CVS), which can be performed at 10 to 12 weeks of gestation, employs removal of a tiny piece of the chorionic villi, the blood vessels that sprout from the blastocyst and form the placenta. It also can detect problems caused by chromosomal or genetic abnormalities. * The quadruple marker screen (QMS), performed at 16 to 19 weeks, can indicate neural tube defects and other problems. In the case of abnormal QMS results, parents may choose further testing. QMS is a screening test rather than a diagnostic test. * A new first trimester screening test for Down syndrome combines ultrasound evaluation of the thickness of the back of the fetus’ neck with maternal blood testing. This test can be done between 10 and 14 weeks of pregnancy. If results indicate increased risk of abnormality, further diagnostic studies can be performed for confirmation. * A fetus with a defect may be carried to term, aborted, or, occasionally, surgically treated in the uterus. Only CVS produces results early enough for a first-trimester abortion.

Answer 159

* Adequate nutrition and stress management are vital for the mother and for the health of the fetus. * Fetal programming therapy looks at how conditions in the womb may influence the risk of adult diseases * Researchers have linked low birth weight to an increased risk of heart disease, high blood pressure, obesity, diabetes, schizophrenia * High birth weight in female infants has been linked to an increased risk of breast cancer

Answer 160

* Prenatal care is crucial to the development of a healthy baby. * A pregnant woman must contact a physician early and visit him or her regularly during the pregnancy to ensure that she is healthy and adequately prepared for pregnancy and childbirth, and that the baby is developing normally. Risks of hereditary conditions are assessed. * Blood samples are drawn to reveal blood type and detect possible anemia and Rh incompatibilities. * If the father is Rh-positive, the mother Rh-negative, and the baby Rh-positive, the baby’s blood will be incompatible with the mother’s. * To avoid antibody formation that would endanger future pregnancies, the mother should receive Rh-immune globulin. * Rh-immune globulin is given to Rh-negative mothers in the third trimester and again after the birth if the baby is found to be Rh-positive. * Pregnant women need increased iron and calcium and adequate intake of all vitamins and minerals—a nutritionally adequate diet. * Because many drugs pass the placental barrier and reach the fetus, pregnant women should avoid all drugs unless specifically prescribed by the physician. * Some drugs are dangerous to the fetus because the fetus is in the act of developing; others are dangerous because an adult dose is a massive dose for a fetus. * Exposure to radiation, viral infections such as rubella, and some drugs (teratogens) during the first trimester can lead to congenital malformations—damage to eyes, ears, or limbs. * Prenatal exposure to alcohol can lead to fetal alcohol spectrum disorder (FASD), characterized by mental impairments, small head and body size, distinctive facial features, congenital heart defects, defective joints, impaired vision, and abnormal behaviour patterns. Researchers doubt that any level of alcohol consumption is safe, and they recommend total abstinence during pregnancy. * Tobacco use during pregnancy increases the risk of miscarriage, low birth weight, infant death, and may cause genetic damage or physical deformities. High levels of nicotine in the mother’s bloodstream can cause fetal hyperactivity, possible metabolizing of cancer-causing by-products of tobacco by the fetus, and poor lung function at birth. Exposure to second-hand smoke after birth increases a baby’s susceptibility to pneumonia and bronchitis. If a mother who smokes is breastfeeding, her infant is exposed to tobacco chemicals through breast milk. * Caffeine stresses both mother and fetus by raising the level of the hormone epinephrine. It also reduces blood supply to the uterus. * Some prescription drugs, illicit drugs, chemicals, and pollutants can be dangerous to the fetus. * Infections that can be dangerous to the fetus include: * Group B streptococcus (GBS), the most common cause of life-threatening infections in newborns. It can cause pneumonia, meningitis, and blood infections. * Rubella, which can cause physical or mental disabilities. Immunization against measles is dangerous to a fetus and must be performed before conception. * Syphilis, which can kill a fetus or lead to the birth of an infected baby. Penicillin will cure the syphilis. * Gonorrhea, which can cause blindness at birth. Erythromycin ointment placed in newborns’ eyes will destroy the bacteria. * Hepatitis B, which can be passed from mother to infant. An infant born to an infected mother can be immunized shortly after birth. * Herpes simplex, an STI that can damage the eyes and brain and for which no cure has been discovered. Having active herpes is one reason for a Caesarean section, which allows the baby to avoid contact with the lesion. It is important to know if the pregnant woman or her partner has a history of herpes. If the woman has not had herpes, but her partner has, she may be at increased risk for contracting the infection and having the initial outbreak during the pregnancy. * HIV, which causes AIDS. It can be transmitted from an HIV-infected mother to the fetus during pregnancy, labour and delivery, and breastfeeding. Antiviral drugs, given to an HIV-infected mother during pregnancy and delivery and to her newborn immediately after birth, reduce the rate of HIV transmission from mother to infant from 25% to 5% or less. • Physical activity should be continued during the pregnancy, for both physical and mental energy. Normal activity will not harm the fetus. • Regular exercise appears to improve a woman’s chance of an on-time delivery and may reduce the risk of pregnancy-related diabetes. Thirty minutes of moderate exercise most days is recommended, unless physical complications prevent exercise. • Pregnant women need to balance exercise with adequate rest and sleep. • Regular cardiorespiratory endurance exercise is recommended. • Kegel exercises and overall exercise classes may aid in the delivery by strengthening the muscles involved. • Childbirth classes have become a routine part of pregnancies; they allow both parents to practice for the delivery. • These classes are designed to teach the details of the birth process as well as relaxation techniques to help deal with the discomfort of labour and delivery. In addition, fathers learn how to be supportive and coach their partners through the delivery; nowadays, fathers often are present at the delivery.

Answer 161

* Complications of pregnancy can prevent full-term development of the fetus or affect the health of a newborn. About 31% of mothers-to-be suffer complications during pregnancy. * Ectopic pregnancy occurs when a fertilized egg implants itself somewhere other than the uterus, usually in the fallopian tubes. * PID often blocks tubes, leading to ectopic pregnancies. The oviduct may rupture if the embryo continues to grow. Sharp pain in the lower back or in one side of the abdomen, often with irregular bleeding, can signal ectopic pregnancy. * Severe bleeding can be extremely dangerous, even fatal. Resulting in 9% of all maternal deaths. * If diagnosed early, before the oviduct ruptures, ectopic pregnancy often can be successfully treated without surgery with injections of methotrexate. * Spontaneous abortion, or miscarriage, ends 10% to 40% of all pregnancies. Most are due to chromosomal abnormalities and occur between the sixth and eighth weeks of pregnancy. * Stillbirth or the delivery of a fetus that shows no signs of life, also called fetal death, fetal demise, stillbirth, and stillborn. In Canada rates of stillbirth are more than 6 in 1000. * Risk factors include; smoking, advanced maternal age, obesity, multiple gestations and chronic disease. * Preeclampsia is characterized by high blood pressure, leaking of protein into urine, and edema (fluid retention), which typically causes swelling of the hands and feet. * Symptoms may include sudden weight gain, severe headache, abdominal pain, blurred vision, and swelling. * If not treated, the disorder can cause seizures (eclampsia). Liver and kidney damage, poor fetal growth, and fetal death are also potential problems from preeclampsia. * Treatment includes bed rest or hospitalization for close monitoring for seizures, and in severe cases early delivery * Placenta previa, the placenta completely or partially covers the cervical opening preventing the mother from delivering vaginally. Often presenting as painless bright red bleeding. * Placental abruption is when a normally implanted placenta prematurely separates from the uterine wall, usually accompanied by abdominal pain, vaginal bleeding, and uterine tenderness. Risk factors include maternal age, tobacco smoking, cocaine use, multiple gestation, trauma, preeclampsia, hypertension, and preterm premature rupture of membranes. Abruptions also increase the risk of fetal death. * Gestational diabetes (GDM) refers to when the body loses its ability to use insulin properly. It can lead to preeclampsia, polyhydramnios (increased levels of amniotic fluid), large fetuses, birth trauma, operative deliveries, perinatal mortality, and neonatal metabolic complications. * Preterm labour is when a woman goes into labour before the 37th week of gestation. About 30-50% preterm labours resolve themselves.

Answer 162

* Labour induction may be necessary if the pregnancy continues well beyond the baby’s due date. * Low-birth-weight (LBW) and premature birth babies weigh less than 2.5 kilograms at birth. They may be premature or small at birth even if full term (small-for-date). * Many organs of a premature infant are not sufficiently developed; this may cause problems with breathing and eating. These infants may face physical and intellectual problems as they grow. * Adequate prenatal care is the best prevention. * Canada ranks very low among the world’s developed countries for low infant mortality (approximately 5 per 1000). Poverty and inadequate health care are key causes. Improvements are needed in the provision of prenatal care and adequate health care and immunizations for infants and young children. * Parents can prevent sudden infant death syndrome (SIDS) by placing sleeping infants on their backs; by eliminating exposure to tobacco smoke, alcohol, and other drugs; by not using a soft mattress; and by keeping a baby’s room cool in temperature. * Coping with loss can lead to deep grief * Feelings of shock, disbelief, and numbness may be common * For the mother, physical exhaustion and hormone imbalances can compound the emotional and physical stress

Answer 163

• Choices in childbirth include type of practitioner, place, and medical practices. • Either a physician or a midwife can deliver the baby. • Births can take place in hospitals or in freestanding birth centers; hospitals usually offer alternative birth centers as well as more traditional delivery rooms. The number of babies delivered by family physicians is decreasing while the number delivered by midwives is increasing.

Answer 164

* Labour begins when hormonal changes in the mother and the baby cause strong rhythmic uterine contractions * Contractions exert pressure on the cervix and cause effacement and dilation * The entire process of labour and delivery depends on a number of factors, but typically takes between 2-36 hours * Mucus plug is expelled;‘water breaks’ * Transition, signifies the last part of the first stage of labour * 60-90 sec contractions; 1-3 min in frequency

Answer 165

* The birth process occurs in three stages. * First-stage labour averages 13 hours for a first birth. * Hormonal changes cause strong, rhythmic uterine contractions that exert pressure on the cervix; the lengthwise muscles of the uterus pull on the circular muscles of the cervix, causing effacement and dilation. * Contractions begin at intervals of 15 to 20 minutes and last about 30 seconds; they pressure the baby to descend into the mother’s pelvis. * The mucus plug is expelled, and the amniotic sac may rupture. * Transition, the end of the first stage of labour, is characterized by strong and frequent contractions, leading to complete dilation.

Answer 166

* When the cervix is completely dilated, the second stage, expulsion, begins. * The baby is slowly pushed into the birth canal, and the mother bears down with the contractions to help the baby move. * As the baby squeezes through the pelvis, its skull bones move together and overlap. The baby is said to be “crowning” when the head appears at the vaginal opening. * The head is usually delivered first, and then the shoulders and body are delivered with the next few contractions. The baby’s chest expands, and the lungs fill with air. * The umbilical cord is cut when it stops pulsating.

Answer 167

* The third stage of labour is the delivery of the placenta, which generally occurs within 5 to 20 minutes of the baby’s birth. * Remnants of the placenta in the uterus can cause infection and bleeding. * The baby is assessed at 1 and 5 minutes after birth using the Apgar scale, which rates five criteria: skin color, heart rate, respiration, reflex irritability, and muscle tone. * Most newborns are tested for 29 specific disorders—some of which are life threatening.

Answer 168

* The medical intervention for pain relief used most often during labour and delivery is the epidural. * Communicate with the obstetrician or midwife * Breathing techniques * Hypnosis * Medication that reduces the transmission of pain signals to the brain is given through a catheter placed between the vertebrae in the lower back. * Local anesthetics are given in low concentrations to minimize weakening of the leg muscles, so the mother can effectively push during the birth. * Women can also choose to have narcotics given for pain relief, but these medications usually provide less relief than the epidural, and, if given shortly before birth, can cause the baby to be less vigorous at birth. * Local anesthesia is available for repair of any tear or episiotomy if the mother has not used an epidural.

Answer 169

* If the baby cannot be delivered vaginally, it can be removed through a surgical incision in the abdominal wall and uterus, a procedure called a Caesarean section. * Caesarean sections are performed to protect either the baby’s or the mother’s health * Caesarean sections are more common among women who are overweight or have diabetes. * Baby head is too big * Baby is in bad position * Mom has high blood pressure * Abnormal or difficult labour * Fetal distress * Dangerous infections * A growing number of Caesarens are performed on low-risk mothers; researchers hope further analysis will help determine whether the trend is due to patient choice, physician choice, or a combination of the two. * A Caesarean section is major surgery but is a relatively safe procedure. * Repeat Caesarean deliveries occur at a rate of 90%.

Answer 170

• The postpartum period, about 3 months after childbirth, is a time of adjustment. -After vaginal deliveries, the mother usually goes home within 1 to 3 days; after a Caesarean section the average is 3 to 5 days.

Answer 171

* Lactation, the production of milk, begins about 3 days post-childbirth * Colostrum is produced prior to lactation * Canadian Paediatric Society recommends 6 months of exclusive breastfeeding * For some women, breastfeeding can be difficult * Lactation begins about 3 days after childbirth. Breastfeeding suits the baby’s nutritional needs and digestive abilities and supplies antibodies. It also reduces the incidence of infant ear infections, allergies, anemia, diarrhea, and bacterial meningitis. * Breastfed babies are less likely to be overweight when they reach preschool age. * About 89% of mothers breast-feed their infants. * Bottle-feeding is sometimes the only alternative, and it can be part of a loving parent-child relationship. It can also allow the father or another caregiver to share in nurturing the child and is less restrictive than breastfeeding. * If a mother does not nurse her baby, she will generally start having menstrual periods again in about 10 weeks. Breastfeeding may delay them for up to 6 months. Breastfeeding does not provide reliable contraception.

Answer 172

* Changes in hormone levels during the postpartum period can cause fluctuating emotions, anxiety, and even severe depression. These generally last only a few weeks and can be relieved somewhat by support from caring family and friends. * An emotional low that may be experienced by the mother following childbirth * Rest, sharing feelings and concerns with others, and relying on supportive relatives and friends for assistance can be helpful

Answer 173

* Strong emotional tie that grows between the baby and the adult who cares for the baby * A secure attachment relationship helps the child develop and function well socially, emotionally, and mentally

Answer 174

* The benefits of physical activity and sport participation cannot be understated. * While moms recognize the importance of physical activity for their health and wellbeing, they often prioritize the needs of their children, household, or employer above their own (Hamilton & White, 2010; Krouse et al., 2011). * Women report significant decreases in their physical activity levels after giving birth to their first child (McIntyre & Rhodes, 2009). * Up to 75% of moms experience barriers to regular physical activity, including lack of time and social support, fatigue, childcare, and obligations to other roles (Verhoef & Love, 1992).