Chapter Three

Question 1

The most vulnerable time for teratogens is when?

Answer 1

teratogens (substances or agents that can cause malformations or functional abnormalities in a developing embryo or fetus) is generally considered to be during the embryonic period, which spans from the third week to the eighth week after conception. This is the critical period when organogenesis (formation of organs) occurs, and exposure to teratogens during this time can have significant and lasting effects on the developing fetus.

Question 2

What is the Apgar test?

Answer 2

The Apgar test is not designed to assess infant intelligence. The Apgar test is a quick assessment tool used to evaluate the physical condition of a newborn immediately after birth. It was developed by Dr. Virginia Apgar and is named after her.

The Apgar test evaluates five criteria:

Appearance (skin color)
Pulse (heart rate)
Grimace response (reflexes)
Activity (muscle tone)
Respiration (breathing rate and effort)
Each criterion is scored on a scale of 0 to 2, and the scores are summed to give a total Apgar score, which can range from 0 to 10. The test provides a quick snapshot of the newborn’s overall well-being and helps healthcare professionals determine if any immediate medical interventions are needed. It does not assess cognitive abilities or intelligence.

Question 3

What is trophoblast

Answer 3

The trophoblast is the outer layer of cells in the blastocyst, which is the early stage of development in a fertilized egg before it implants into the uterus

Question 4

what is blastocyst

Answer 4

Blastocyst: The morula continues to divide, and a fluid-filled cavity develops within it. This results in the formation of a blastocyst, which has an outer layer of cells called the trophoblast and an inner cell mass.

Question 5

What is Cephalocaudal development

Answer 5

Cephalocaudal development refers to the pattern of growth and development that occurs from the head (cephalic region) to the tail or feet (caudal region). In cephalocaudal development, growth typically occurs in a sequential and directional manner, with the head developing first, followed by the lower parts of the body.

Question 6

What is proximodistal development

Answer 6

Proximodistal development refers to the pattern of growth and development that occurs from the center or core of the body (proximal) outward toward the extremities (distal). In proximodistal development, control and coordination of the central parts of the body develop before those of the peripheral parts.

Question 7

Germinal Period

Answer 7

Period of prenatal development that takes place in the first two weeks after conception.
Includes the creation of the fertilized egg (zygote), followed by cell division and attachment of the zygote to the uterine wall

Question 8

blastocyst

Answer 8

the inner layer of cells that develops during the germinal period. These cells later develop into the embryo

Question 9

Trophoblast

Answer 9

the outer layer of cells that develops in the germinal period. These cells provide nutrition and support for the embryo

Question 10

Embryonic period

Answer 10

a period of prenatal development that occurs 2-8 weeks after conception. The rate of cell differentiation intensifies, support systems for the cells from, and organs appear

Question 11

amnion

Answer 11

prenatal life support system that is a bag or envelope containing a clear fluid in which the developing embryo floats

Question 12

umbilical cord

Answer 12

A life-support system that contains two arteries and one vein and connects the baby to the placenta

Question 13

placenta

Answer 13

a life-support system that consists of a disk-shaped group of tissues in which small blood vessels from the mother and offspring intertwine

Question 14

organogenesis

Answer 14

Organ formation that takes place during the first two months of prenatal development

Question 15

The fetal period

Answer 15

lasting about 7 months. in the prenatal period between two months after conception and birth in typical pregnancies

Question 16

teratogen

Answer 16

is any agent that can potentially cause a birth defect or negatively alter cognitive and behavioural outcomes. (tera means monster). So many teratogens exist that practically every fetus is exposed to at least some teratogens. It’s difficult to know which teratogen causes which problems

Question 17

Teratology

Answer 17

The field of study that investigates the causes of birth defects is called teratology. 3 things effect the severity.

1) dose - the greater the dose of an agent, such as a drug, the greater the effect

2) Genetic susceptibility - e.g how a mother metabolizes a certain drug influences the degree to which the drug effects are transmitted

3) Time of exposure - teratogen exposure does more damage when it occurs at some points in development than at others. In general the embryonic period is more vulnerable than the fetal period

Question 18

Prescription drugs

Answer 18

prescription drugs that can function as teratogens include antibiotics, some antidepressants, certain hormones, accutane.

Non prescription drugs - diet pills, high dosages of aspirin

Question 19

Psychoactive drugs

Answer 19

caffeine - seems okay during pregnancy

alcohol - heavy drinking can lead to fetal alcohol spectrum disorder

nicotine - prenatal development, birth, postnatal development - preterm birth, low birth weight, fetal and neonatal death and respiratory problems and SIDS are more common among the offspring of women who smoked

cocaine - lower birth weight, length and head circumference, lower arousal , higher excitability, lower reflexes, attention and behaviour problems

Question 20

Incompatible Blood Types

Answer 20

Incompatibility between the mother and father’s blood types poses another risk to prenatal development.

If a surface marker called the Rh-Factor, is present in an individual’s red blood cells they are Rh-positive, if the Rh-marker is not present, they are Rh-negative.

If a pregnant woman is Rh-negative and her partner is Rh-positive, the fetus may be Rh-positive. If the fetus is Rh-positive and the mother is Rh-negative, the mother’s immune system may produce antibodies that will attack the fetus. - this can result in miscarriage, stillbirth, anemia , jaundice, heart defects, brain damage or death soon after birth.

The first baby is generally not at risk , but with each pregnancy the risk increases. A vaccine rhoGAM may be given to the mother within 3 days of the child’s birth to prevent her body from making antibodies that will attack any future Rh-positive fetuses in subsequent pregnancies.

Question 21

Environmental Hazards

Answer 21

examples - radiation, toxic wastes, chemical pollutants

Question 22

Maternal dieseases

Answer 22

E.g. rubella (german measles) can cause prenatal defects.
Syphilis is damaging later in prenatal development includes eye lesions which can cause blindness.
Genital herpes can contract when through the birth canal.
AIDS - infect baby during gestation across placenta 2)during delivery 3) post partum through breastfeeding

Question 23

Maternal Diet

Answer 23

folic acid a complex b vitamin lowered preterm labour risk , lower behaviour problems in toddlers, lower risk of spina bifida

Question 24

Maternal age

Answer 24

mortality rate of infants born to adolescent mothers is double that of infants born to mothers in their twenties.

older maternal age is linked to risk of down syndrome

Question 25

Paternal Factors

Answer 25

Men’s exposure to lead, radiation, pesticides, petrochemicals may cause abnormalities in sperm that lead to miscarriage or diseases such as cancer.

Question 26

Stages of Birth

Answer 26

The birth process occurs in three stages. The first stage is the longest of the three.

Second stage when baby’s head starts to move through the cervix and the birth canal lasts until the baby is out of the mothers body.

Afterbirth is the third stage, the placenta, umbilical cord and other membranes are detached and expelled.

Question 27

Medication for birth

Answer 27

analgesia: relieves pain

Anesthesia: block sensation in an area of the body or to block consciousness.

oxytocin/pitocin: induce labour

Question 28

Apgar Scale

Answer 28

widely used to assess the health of newborns at 1 and 5 minutes after birth.

Evaluates heart rate, respiratory effort, muscle tone, body colour, reflex irritability.

Score 7-10 - babies health is good.
5 - may be developmental difficulties
3 or below - signals emergency and baby might not survive.

Question 29

Brazelton Neonatal Behaviour Assessment (NBAS)

Answer 29

24-36 hours after birth. A sensitive index of neurological competence up to one month after birth .
Assesses the neurological development, reflexes, and reactions to people and objects.
16 reflexes such as sneezing, blinking, rooting are assessed.

Question 30

Neonatal Intensive Care unit network of Neurobehavioural scale (NNNS)

Answer 30

assessment of neurobiological and stress responses, regulatory capacities.
NBAS assess normal healthy full term babies, NNNS is used for evaluating preterm infants.

Question 31

Preterm and Small for Date infants

Answer 31

low birth weight, preterm delivery, small for date … three related conditions .

Consequences of preterm birth and low birth weight - higher rates of illness and developmental problems than infants of normal birth weight.

Question 32

Kangaroo care

Answer 32

Can stabilize infants heartbeat, temperature and breathing

Question 33

low birth weight

Answer 33

infant that weighs less than 5.5 pounds at birth

Question 34

preterm

Answer 34

born before 37 weeks gestation

Question 35

small for date

Answer 35

birthweights below normal

Question 36

postpartum period

Answer 36

about 6 weeks