Fetal Development Flashcards
Embryo
<10 Week Gestation
Fetus
10 weeks to birth
Pre Term Baby
A baby is born <37 weeks gestation
Term Baby
A baby born between 38-42 weeks gestation
Post Term Baby
Baby is born after 42 weeks gestation
Trimesters
1st Trimester: < 12 weeks
2nd Trimester: 13-28 Weeks
3rd Trimester: > 28 Weeks
Process of Fertilization
- Sperm locates the egg
- Fertilization occurs
- Zygote travels to uterus
The blastocyst combines with what
The blastocyst will combine with tissues from the endometrium to form the chorionic membrane (outermost part of the fetal membrane
How does the amniotic sac form
The outer tissue will envelop the embryonic structure to form the amniotic sac
The amniotic sac will surround the entire embryo
Umbilical Stalk
The embryo attaches via the umbilical stalk which develops into the umbilical cord
Chorionic Villi
The umbilical cord connects to the finger-like projections in the outer lining of the chorion (chorionic villi)
The chorionic vili from the embryonic blastocyte will expand and grow to become the placenta
There will be two parts: Maternal compartement and Fetal Compartment
What are the different germ layers
Ectoderm
Mesoderm
Endoderm
Ectoderm
Outer layer
Central Nervous System: brain and spinal cord
Peripheral Nervous System: cranial nerves and spinal nerves
Sensory epithelia of the eyes, inner ears, and nose
Glandular Tissues: posterior pituitary gland, adrenal medulla
Mesoderm
Middle Layer
Cardiovascular System: Heart and Blood Vessels
Lymphatic system vessels
All Connective Tissue
All Muscle Tissue
Kidneys and ureters, spleen
The three major body cavities: pericardium, left and right pleura, and peritoneum
Serous linings of organs within the body cavities
ENDODERM
Innermost layer
Digestive System
Respiratory System: pharynx, lungs, and epithelial lining of the trachea and lungs
Embryonal Stage of Development
Will have the development of the trachea and major bronchi
Birth at this stage can result in laryngeal, tracheal, or esophageal atresia or stenosis
The baby will often be trached in order to have the trachea dilated
PSEUDOGLANDULAR PHASE
Development of remaining conducting airways
There is the incomplete development of the lungs characterized by an abnormally low number and/or size of bronchopulmonary segments and/or alveoli (hypoplasia) can develop
There will also be lung hypoplasia with diaphragmatic hernia
CANNICULAR PHASE
Development of vascular bed and framework of respiratory acini
When the fetus is born premature with inadequate developed airways with a surfactant deficiency (lack type II pneumocytes) will lead to RDS
SACCULAR PHASE
Increased complexity of saccules
ALVEOLAR PHASE
Development of alveoli
Stages of Human Intrauterine Lung Growth
- Embryonal
- Pseudoglandular
- Canalicular
- Saccular
- Alveolar
Post Birth
Alveoli and arterial support will continue to increase in size and number throughout infancy and childhood
More than 80% of the eventual total number of alveoli (~300 million) will form after birth
Alveolar growth will form mostly during the first year and a half
Infants will double in in body weight by 6 months and triple by 1 year
Oxygen uptake will increase proportionally
Factors Affecting Lung Development
Glucocoid Steroids
Twins
Maternal Diabetes
Decrease Amniotic Fluid
Factors Affecting Lung Development
Glucocorticoid Steroids
Accelerate lung maturation (Type II pneumocytes)
The steroid betamethasone may be given to mom if we are worried about a premature baby
Factors Affecting Lung Development
Maternal Diabetes
Slows lung tissue maturation
Pneumocyctes Analysis
Amniotic fluid can be analyzed for pneumocytes
Pneumocyctes Type I
Lays out the structure
Squamous cells
Thin flat membrane that is permeable to gas
97% of alveolar surface area
Pneumocyctes Type II
Surfactant production
Can differentiate and become type I cells
Cuboidal
Will appear ~22-24 weeks gestation
Surfactant Composition
Surfactant is composed of phospholipids, neutral lipids, and proteins
Mammalian Fetal Lung Fluid Composition
- 90-95% Lipids
- 80-85% phospholipids
- Phophatidylcholine is the most abundant phospholipid (75-80%)
- Dipalmitoylphosphatidlychoine (50%)
- 1-palmitoyl-2-oleoyl-phosphatidylcholine
- 5-10 % proteins
- 80-85% phospholipids
Bovine– BLES- very similar to human surfactant
FETAL LUNG FLUID FUNCTION
The presence of fetal lung fluid is essential for normal lung development
Fetal lung fluid will promote lung growth and maintain the shape of airways through keeping them filled with fluid. Allows the patency of potential spaces and the development of FRC.
Fetal airways are not collapsed but filled with fluid from the canalicular period until the delivery and the initation of breathing air
The lungs will have breathing like movements, but there is no function until the first breath of air
FETAL LUNG FLUID AND SECRETION
The lungs will secrete fluid from the lower respiratory tract (terminal respiratory units) up the conducting airways into the oropharynx where it will be swallowed or join with the amniotic fluid
The baby will produce ~250-350 mL/day
At tern fetal lung fluid levels will peak at 30 mL/kg which is the equivalence of the volume of FRC
FETAL LUNG FLUID AND AMNIOTIC FLUID
The lungs will secrete fluid from the lower respiratory tract (terminal respiratory units) up the conducting airways into the oropharynx where it will be swallowed or join with the amniotic fluid
This is why we can test the amniotic fluid for information about fetal lung fluid
The concentration of phosphatidylglyceroland phosphatidylcholine in amniotic fluid is a sensitive indicator for the state of fetal lung maturity
The fetal lung fluid will have a lower pH than amniotic fluid
The baby will produce ~250-350 mL/day
At tern fetal lung fluid levels will peak at 30 mL/kg which is the equivalence of the volume of FRC
Lung fluid is removed from the lung via decreased production prior to birth (hormones), contractions during labor, and lymphatic absorption after birth
If there is lung fluid retention it can lead to respiratory issues such as transient tachypnea of the newborn
Fluid retention problems can be seen with c-sections
The treatment of TTHN is CPAP and O2 therapy (24 hours)
LUNG FLUID RETENTION
- Lung fluid is removed from the lung via decreased production prior to birth (hormones), contractions during labor, and lymphatic absorption after birth
- If there is lung fluid retention it can lead to respiratory issues such as transient tachypnea of the newborn
- The treatment of TTHN is CPAP and O2 therapy (24 hours)
- Fluid retention problems can be seen with c-sections
Diseases that Effect Surfactant
Aspiration Syndrome
Ex. Meconium, blood, amniotic fluid
Meconium can inactivate surfactant as well as decrease the production of surfactant
Pulmonary Hemmorrhage or Edema
Deactivation of surfactant
Pulmonary Hemmorrhage or Edema
Risk Factors
PDA is a risk factor
Large differences in systemic to pulmonary vascular pressure between the descending aorta and pulmonary vasculature
Fetal Lung Maturity Tests
L/S Ratio
L/S Ratio
Looks at the componenets of surfactant
The levels of spingomyelin will remain constant in th eamniotic fluid, whereas the levels of lecithin will increase as the fetal lung matures and produces surfactant
This test will be done through amniocentesis or when mom’s membrane is ruptured
L:S Ratio Values
The lecithin/sphingomyelin ration (L:S Ration) is usually 1:1 by week 31-32 and 2:1 by 35 week gestations
- L:S 2:1 or greater
- Lungs are mature
- L:S 1.5-1.9 : 1
- 50% chance of RDS
- L:S less than 1.5 : 1
- High risk of RDS
CARDIOVASCULAR DEVELOPMENT
The heart will begin to beat regularly early the fourth week after fertilization
Will be from the mesoderm
The heart is the first organ that will be fully formed
At week 8 the heart will be fully developed
At 21 days there will be the fusion of the tubes
FETAL CIRCULATION AND PVR
- Fetal circulation will be very different from adult circulation as the blood is mostly shunted around the lungs
- There is highly vascularized resistance in pulmonary circulation in the fetus
- One of the reason there is high PVR is because of the vasoconstriction in response to PaO2
- The other reason for high PVR is the fluid in the lungs will be pressing down on the vasculature
- The pressures will be high in the pulmonary system that blood will back up into the right side of the heart increasing pressures in both the right ventricle and atrium
- The right ventricle is unable to pump through this resistance so it will go through the foreman ovale
FETAL CIRCULATION AND SVR
There is a low vascular resistance in systemic circulation
The placenta is a large surface area/volume with a low resistance
UMBILICAL VEIN
Return oxygenation blood from the placenta
Enters the fetal body through the umbilicus to the undersurface of the liver then to the branches (2 or 3) to the liver
Continues on to the ductus venosus
DUCTUS VENOSUS
Allows blood (30-50%) returning from the placenta to bypass the liver
Drains into the inferior vena cava which goes into the right atrium
FORAMEN OVALE
- An opening in the septum between the two atriums
- Blood from the inferior vena cava will be deflected from the right atrium into the left atrium
- Some of the blood will not be shunted through the foramen ovale and rather will go to the right ventricle then into the pulmonary artery
- But most blood will not flow into the lungs and will be diverted into the ductus arteriosus
DUCTUS ARTERIOSIS
A small vessel that connects the pulmonary artery with the descending (thoracic) aorta
It allows more blood to detour into the systemic circulation without going through the fetal lungs
UMBILICAL ARTERIES
There are two umbilical arteries
Extensions of the internal iliac arteries
Will carry deoxygenated fetal blood into the placenta
The Placenta
The placenta is the only source of oxygen and nutrient rich blood for the baby. It is also the only way for the baby to remove deoxygenated blood
This occurs via finger like projections in the placenta pool
Pathway of the Placenta to the Right Atrium
- Placenta
- Umbilical Vein
- Will branch into two
- One branch to the liver (venous admixture) and then to the IVC
- The other branch goes directly to IVC (shortcut via ductus venous) (oxygen rich blood)
- IVC (venous admixture from legs and PaO2decreases also from the liver)
- RA
Fetal Circulation Superior Vena Cava
The SVC bring deoxygenated blood from the head and arms to the right atrium adding more venous blood into the right atrium and decreasing PaO2
UMBILICAL CORD
Contains 3 vessels (2 small arteries and 1 large vein) which will be surrounded by a tough gelatinous material (Wharton’s Jelly)
This jelly will prevent the cord from being squished or bent
Blood from the Umbilical Cord
- Contains hemtopaotic stem cells, which can be frozen and used to treat infant cancers
- The RTs will run cord blood
- Respiratory acidosis indicates distress of the fetus and an assessment of the baby is required
Fetal Circulation
Atrial Septum
There is a two layered wall in the atrial septum which is composed of the septum secondum and the septum primum
Both walls will have holes in them s when pressure is increase a flap will be created between the holes (Foramen ovale) connecting the two atriums
Basic Fetal Blood Flow
Placenta (~SaO290%) - Umbilical vein (~SaO280%) - Ductus venosus (~ SaO270%) âIVC - RA (~SaO255% to 65%) - FO - LA - LV - aorta with some blood, between 13 to 25%, going into pulmonary circulation via
RA - RV - pulmonary trunk - Ductus arteriosus - aorta
AMNIOTIC FLUID
Will be continuously produced, used, absorbed, and exchanged throughout pregnancy
A term fetus will swallow about 500 mL of amniotic fluid a day and excretes the same amount of hypotonic urine back into the mis each day
There will be ~30mL of amniotic fluid at 10 weeks
At term there will be 1.5 L
Amniotic Fluid Functions
Protect the fetus from injury by acting as a cushion
Controls the thermal environment
Assists in the effacement and dilation of the cervix during labor
Amniotic Fluid Composition
Maternal blood products
Amniotic cells
Fetal skin, hair, and urine
What is the gas exchange unit of the fetus
the placenta
Maternal Blood
Maternal blood will have a high PO2 and a low pH
Shifts in the oxyhemoglobin curve to the right decreasing the affinity of maternal Hgb for O2
This allow for easy offloading of oxygen to the fetal blood
The low pH is due to extra CO2and the fact that mom has a big belly and it become harder to breathe (pregnancy is a restrictive lung process)
Fetal blood
Fetal blood has a low PaO2
Shifts the oxyhemoglobin curve to the left allowing easy uploading of O2 by fetal blood
Fetal hemoglobin has the ability to combine with oxygen to a greater extent than adult hemoglobin
PRENATAL CARE
Also known as antenatal care, and is medical care recommened for women during pregnancy
Should begin at 6-8 weeks of pregnancy
Purpose: To identify any potential problems [normal/low risk or high risk] and to intervene in a timely manner
PRENATAL CARE INCLUDES
Maternal history & risk factors: Genetic disorders, infectious disease, etc.
Antenatal assessment
Intrapartum monitoringàex: ultrasound
MATERNAL HISTORY & RISK FACTORS
Age
Too young = risk of spontaneous abortion or poor prenatal care
Too old = risk of genetic disorders (ex. Down syndrome)
MATERNAL HISTORY & RISK FACTORS
Lifestyle
- Tobacco cessation counselling
- Asthma
- Due to the hormonal changes during pregnancy women will tend to lose control of their asthma and fear being on corticosteroids thinking it will hurt the baby but research shows it is safe for the baby
- Acute Care for in case mom gets sick
- Every mother should have the flu shot
- Maternal diabetes
- Drug use
VIABILITY OF THE FETUS
- Will be dependent upon the stability and maturity of
- CNS
- Including protective mechanisms
- Circulatory system
- Respiratory system
- Musculoskeletal system
- Integrity of the skin will help determine how susceptible the infant is to infections
Ultrasounds (Sonography)
The first ultrasound will be done around the 11-14 week mark and used to predict a due date
2nd ultrasound will be done at 18-20 mark and can determine sex of the baby as well as look for any anatomical concerns, viability, and estimate gestational age
NUCHAL TRANSLUCENCY SCAN
Ultrasound that looks at the nuchal folds in the neck of the fetus
Done at 11-14 week of pregnancy when there is an increase risk in the pregnancy
A wider fold = chromosomal defect
Will have a 70% detection rate of Down Syndrome
AMNIOCENTESIS
Invasive test where a needle will pierce the amniotic sac to obtain an amniotic fluid sample
done in conjunction with an ultrasound at ~15-18 week
Done when there is something that will make the fetus not viable in order to give mom time to plan if they have to do a late abortion
Can have false positives
Will use a needle to pierce and obtain amniotic fluid sample
AMNIOCENTESIS Will Test For
Lung Maturity
Gender
Rh isoimmunization
Chromosomal abnormalities [trisomy 21]
Fetal enzyme deficiencies
Certain genetic mutations
Spina bifida
Bleeding disorders
Nonstress Test (NST)
Assess for spontaneous movement by measuring fetal heart rate
When the fetus move the heart rate will increase
In a 20-30 minute period a reactive (good) test means that the heart rate will increase twice for at least 15 BPM for 15 seconds with maternal perception of fetal movement
Reflect normal uteroplacental function and predicts normal fetal survival
Contraction Stress Test (CST)
Assess viability of uterus and placenta
Monitors fetal HR during an induced contraction (oxytocin). The contraction is used in order to put stress on the fetus and assess a response
Indicated when there is a lack of movement noted late in the pregnancy
A positive test indicated that more the 50% of contractions result in late decelerations (poor outcomes)
BIOPHYSICAL PROFILE [BPP]
- Done at the 26-28 mark
- Indications: Maternal diabetes, hypertension, low fetal movement
- Scores
- 8-10 Normal
- 6= Uncertain repeat test
- 0-4= Abnormal
BIOPHYSICAL PROFILE [BPP] Measures
- Fetal Breathing: 1 episode of 30 seconds during a 30 minute time
- Normal: Positive
- Abnormal:Absent
- Gross Body Movement: 3 during a 30 minute time
- Normal: 3 or more
- Abnormal:2 or less
- Tone: 1 episode of extension/flexion during a 30 minute time
- Normal: Positive
- Abnormal:Absent
- Reactive NST: 2 episodes of +15 bpm increased in 30 minutes
- Normal: Yes
- Abnormal:No
- Amniotic Fluid: 1 pocket of 1 x 1 cm
- Normal: Positive
- Abnormal:Absent
CHANGES IN THE MOM During Pregnancy
- Nausea and vomiting at 4-6 weeks gestation
- Frequent urination
- Cartilage/joint relaxation and stretching
- Pregnancy will release relaxin
- More flexible but more prone to injury
- Skin changes (acne)
- Fetal movements as early as 16 weeks
- Uterine Enlargement (fundal height)
- Will be determined from ultrasound
- Effacement and dilation
- Breast development for milk production
- Hormonal changes
- Increased respiratory rate and tidal volume (restrive pattern)
- Blood volume increase (40-50%)
- Cardiac output can double or triple by 33 weeks gestation
Hyperemesis Gravida
Severe nausea and vomitting durign preganancy
Fundal height
Fundal height measured from pelvis to rib cage
At 36 weeks the uterus should be a few cm under the rib cage
Hormonal Changes in Mom during preganacy
Increased estrogen progesterone and prostaglandins
Prostaglandin will be used to keep PDA open
SPONTANEOUS ABORTION [MISCARRIAGE]
If occurs in 1st semester
- fetal in origin due to faulty development
If occurs in 2nd semester
- maternal factor (ex. trauma, drugs, cervix not supporting fetus, etc)
ECTOPIC PREGNANCY
- Implantation outside uterus
- Most common in fallopian tubes
- May lead to tubule ruptue which causes a massive hemmorrhage
- If it is an ectopic pregancy will have to have an abortion
MATERNAL DIABETES MELLITUS
Gestational diabetes is abnormal glucose intolerance in pregnancy
Results in greater risk for congenital anomalies, respiratory distress, and electrolyte disorders
With good prenatal care and glycemic control you can expect normal pregnancy outcome
The infant of diabetic mother (IDM) is classically a large plethoric infant (> 4000 gms at birth)
Uncontrollable Gestational Diabetes
Uncontrolled diabetes = maternal hypertension = can lead to uteroplacental insufficiency and polyhydraminos
Diagnosis of Gestation Diabetes
Drink glucose drink, test blood glucose
Higher than 9mmol = indicates gestastional diabtetes
PREECLAMPSIA
Occur after 20 week gestation when >140/90 mmHg or a systolic change >30 mmHg or diastolic >15 mmHg
Unknown etiology
Asmatic women have a higher risk
The ultimate treatment will be the delivery of the baby
Preclapsia Triad
Hypertension
Proteinuria-Frequent urination
Edema
Preclampsia BP
systolic change greater 30 mmHg
Dys change of 15 mmHg
Bp greater than 140/90 mmHg= preeclampsia
Mild Preeclampsia Treatment
Mild preeclampsia may be treated with bed rest, low dose aspirin, salt restrictions, and frequent monitoring
Severe Preeclampsia Treatments
If severe, MgSO4 is added to lessen risk of seizures and as a smooth muscle relaxant
Preeclampsia Major Complications
Abruption and HELLP syndrome (hemolysis, elevated liver enzymes, low platelets)
Delivery should be managed quickly with antihypertensive agents in place
ECLAMPSIA
Eclampsia is a sudden progression of preeclampsia where the patient goes into a coma or convulsive seizures
Can occur post-partum if patient had preeclampsia
Eclampsia Treatment
- The routine for preeclampsia
- Quick delivery of the fetus
- Treatment of symptoms
Oligohydramnios
- An abnormally small amount of amniotic fluid
- Cause is usually unknown
- Less room for the fetus to grow
- Growth retardation/restriction
- Pul hypoplasia– diaphragmatic hernia
- Agenesis= malformation of organs
OLIGOHYDRAMNIOS Can Lead to
Compression of structures as they are growing
Anomalies (limb deformities, pulmonary hypoplasia, renal and urinary defects or agenesis)
IUGR
Compression of the cord
Fetal demise
POLYHYDRAMNIOS
- Too much amniotic fluid [>2L]
- Can over distend the uterus, leading to premature rupture of membranes [PROM]
- Associated with anomalies like anencephaly (part of skull missing), esophageal atresia, TE fistula, neural tube defects
- Also associated with multiples, hydrops fetalis, maternal diabetes
- Cause is usually unknown
Hydrops Fetalis
abnormal accumulation of fluid in 2 or more units– acites, pl.effusions, pericardial effusions, and skin
ABRUPTIO PLACENTAE
Premature separation [from a minor separation to complete detachment] of a normally implanted placenta from the uterus
Fetal well being can be seriously compromised
Baby or mom can hemorrhage
C Section may be considered for prompt delivery
Etiology is mostly unknown, with a high correlation to preeclampsia
PLACENTA PREVIA
Placental implantation over or near the internal os
From partial occlusion/covering to complete obstruction of the os
If the fetus or maternal condition is endangered then a cesarean section [C-sec] is almost always performed to deliver the fetus
If deemed minor with no compromise àbed rest
A C-sec will be done in a total previa
PLACENTAL INSUFFICIENCY
- Usually in the post term baby as they have grown so big that the placenta can no longer meets it needs
- Placental aging usually only affects third trimester or post term growth [> 42 weeks’ gestation]
- The delivered infant is considered as small for gestational age or intrauterine growth retardation
- Even though they are post term it is because the placenta cant handle it
- The younger the babe, the smaller the babe!!
IUGR [SGA] & LGA
These can give clues for what is happening with the baby
Small for gestational age [SGA] : Birthweight < 10% percentile
Large for gestational age [LGA]: Birth weight > 90% percentile
SMALL FOR GESTATIONAL AGE
Small for gestational age or intrauterine growth restriction(IUGR) is defined as an infant whose weight is below the 10thpercentile or more than 2 standard deviations below the mean for its’ gestational age
SMALL FOR GESTATIONAL AGE
Complications
- Birth asphyxia
- More prone to be breech
- Hypoglycemia
- Polycythemia
- Not developing as they should
- Thermal instability
- Because they are smaller
- Persistent fetal circulation
- This includes PDA, foramen ovale, etc
- Malformations
- Outcomes are based on severity
LARGE FOR GESTATIONAL AGE
- Any infants whose weight for is above the 90th percentile for gestational age
- Usually associated with infants of diabetic mothers but can be seen in infants with anomalies, large infants from large parents, or infants with hydrops
- Due to their size these infants are at greater risk of birth trauma
- Harder to come out of birth cannal
- HIE more common
- Umbilical cord around neck more common
- Complications can include RDS electrolyte imbalances
- Both are mostly in moms with gestational diabetes
CEPHALIC PRESENTATION
Normal presentation
Ideal position
Head facing posteriorly
BREECH PRESENTATION
Coming out feet first due to a failure to turn
Normally this will be identified as a problem before labor
May or may not require c section
TYPES BREECH PRESENTATION
Frank: butt first, feet near head
Complete: knees are bent, feet near butt
Incomplete or Footling: one or both feet stretched out below butt
FACE PRESENTATION
The chin presents first in this position with the neck hyper-extended
If the chin is posterior, vaginal delivery is not possible
BROW PRESENTATION:
Brow presentation usually corrects during pregnancy
Less severe than face presentation
If not, vaginal delivery is not possible
TRANSVERSE OR SHOULDER LIE:
When the fetus presents with the long axis of it’s body not parallel to the mother’s
They could present as should fisrt and if they can be manipulates so that mom can still give birth vaginally
May present shoulder first or may turn as they proceed down the birth canal
If the fetus can be manipulated, vaginal delivery can be accomplished BUT if not, caesarean is the only option
RH (D) ISOIMMUNIZATION
First Pregnancy
An Rh(D) Negative mom is impregnated by a Rh(D) + man
The mom will become exposed to fetal RBC which can leak across the placenta and stimulate antibody production
Will not affect the first pregnancy but will affect subsequent pregnancies
RH (D) ISOIMMUNIZATION
Detection
May be detected on amniocentesis through hyperbilirium
RH (D) ISOIMMUNIZATION
Subsequent Pregnancies
- After the 1stsensitization mom’s antibodies will lyse (kill) fetal RBC leading to life threatening anemia in the fetus
- This hemolytic anemia trigger fetal bone marrow to release erythroblasts into circulation
- Erythroblastosis
RH (D) ISOIMMUNIZATION
Prevention
- Mom can be given Rh(D) immunoglobin (Id D): Rhogam or WinRho immunoglobin
- Usually given at 28 weeks
- This is if we identify the problem before the RBC begin to lace
- Intrauterine transfusions will be given through the umbilicus every 2 weeks
RH (D) ISOIMMUNIZATION
If there is a suspected isoimmunization, the mom is continually tested for Rh levels
If they rise, amniocentesis will be done to monitor bilirubin levels – high levels indicate impending fetal death
RH (D) ISOIMMUNIZATION
Newborns with Erythroblastosis
Newborns with Erythroblastosis fetalis will usually have exchange transfusion done after birth
Severe Erythroblastosis fetalis in a newborn results in hyperinsulinism, edema and fluid overload, heart + liver + kidney failure, RDS
HYDROPS FETALIS
Abnormal accumulation of fluid which can lead to severe life threatening swelling and edema due to blood incompatibility of mom and baby
Abdomen (ascites)
Thorax (pleural effusions)
Pericardiac sac (pleural effusion)
Associated with polyhydramnios (too much amniotic fluid) and placental edema
2 types immune and nonimmune
HYDROPS FETALIS
Immune
Complication of blood group incompatibility between the mother and baby.
This type of hydrops is uncommon, however, because of the widespread use of Rh immunoglobulin treatment for Rh negative women.
HYDROPS FETALIS
Non Immune
This is the more common type. It can result when diseases or complications interfere with the baby’s ability to manage fluid.
Severe anemias
Congenital infections (infections present at birth)
Heart or lung defects
Chromosomal abnormalities and birth defects
Liver disease
HYDROPS FETALIS
SYMPTONS during Pregnancy
Large amounts of amniotic fluid
Thickened placenta
Ultrasound of the fetus shows enlarged liver, spleen, or heart, and fluid buildup surrounding the fetus’ abdomen, heart, and lungs
HYDROPS FETALIS
SYMPTONS After Birth
Pale coloring
Severe swelling overall, especially in the baby’s abdomen
Enlarged liver and spleen
Respiratory distress (difficulty breathing)
Usualy from the huge abdomine but there are also reason affecting bretahing
PREMATURE RUPTURE OF THE MEMBRANES [PROM]
Membrane has ruptured prior term
Preterm baby where the water has broke before the baby is ready to come out
Prolonged rupture of membrane (ROM) for more than 24 hours can lead to a greater risk of infection and sepsis
Diagnosis is confirmed if amniotic fluid is observed outside the cervix in conjunction with the maternal history:
Fever, Malaise, reported ROM
PREMATURE RUPTURE OF THE MEMBRANES [PROM]
When will Labor be induced
- If the fetus is mature enough (36-38 week), labor will be induced
- If not, the mom will be restricted to bed rest, given MgSO4 to prevent contractions (tocolytic)and steroids to improve lung growth as well as antibiotics, amnioinfusion may be necessary
- If they know what they are treating they wll use a specific antibiotic if not it will be a broad spectrum one
DYSTOCIA
Prolonged difficult labor and delivery which is secondary to uterine, pelvic, or fetal factors
When the 1stand 2ndstages of labor exceed 20 hours
DYSTOCIA Causes
- Dysfunction of the uterus
- Contractions are too weak or too strong (obstructing baby from getting out)
- Abnormal fetal presentation
- Breech, brow position, face position
- Fetal head is too large for maternal pelvic opening
- Hydrocephalus
- Abnormalities in size or shape of the birth canal
- Labor that is too long increases mortality of the fetus due to asphyxia, stress, infection
- So we will try to quick fix the underlying problem or do an emergency c section
SHOULDER DYSTOCIA
Can occur in larger infants when the anterior shoulder impinges on the pubic bone (Head is popping out but shoulder is stuck)
Uncommon
Once the head is delivered, the babe is caught by the shoulder and is compressed in the birth canal
Speedy manipulationof the infant and delivery are necessary to prevent further infant stress
Broken collar bones and broken arms are a risk during extraction
Helping Labor Along- Amniotomy
An amniotomy: The doctor ruptures the amniotic sac during a vaginal exam
Once the membranes are broken, and if the cervix is ready, labor starts in a matter of hours.
Induction of Labor
Whenlabor is artificially started with either Prostoglandin or Oxytocin– synthetic hormones that start and progress uterine contractions
Indomethathin can also be used
Usually given orally but can also be given vagially
Induction of Labor
Prostaglandin
Hormone that aids in ripening [soft, thinned out] of the cervix.
A gel inserted into the vagina or a tablet given by mouth.
May be used alone or with oxytocin.
To start the labor
Induction of Labor
Oxytocin
Hormone given to stimulate contractions.
Administered continuously via an IV
Start low dose and increase as needed until labour is progressing well
Usually used to encourage a labour that is stalling.
More than one fetus will increase the risk of
Premature labor
Abnormalities
Growth problems
Because they are sharing that space
Problems with the placenta or cord
Mortality increase
How are multiple gestation diagnosed
But reemmeber not all mom get care duing pregency
Can be diagnosed at the 8-11 week ultrasound
vanishing twin
Some twin pregnancies will only produce one child, a phenomenon termed as vanishing twin
The fetal compartement is absorbed by the other compartment and mom
Multiple Gestation Maternal risk factors
Increased maternal risk factors include: preterm labor, hypertension, placental abruption, anemia, and urinary tract infections
Multiple Gestation Lung Maturity
Prematurity with the average delivery at 32 weeks
Lung maturity is accelerated in multiples
31-32 week gestation twins have the same pulmonary function as average 34-35 week singleton infant
Multiple Gestation Fetal Risks
Twins weighing less than 2500g also have lower mortality rates than comparable singleton infants
Intrauterine growth retardation is also a complication with an incidence of approximately 50-60%
Congenital anomalies are also more common in multiples than with singletons, mostly in monozygotic twins that developed from a single zygote
Anomalies such as conjoined twins and acardia (absence of a heart) are unique to multiple pregnancies
Multiple Gestation
Twin to Twin Transfer
Twin to twin transfusion is also unique to monozygotic pregnancies: a vascular anastomosis occurs via the shared placenta, with 1 twin receiving most of the blood flow
Clinically a twin to twin transfusion is diagnosed via US when there is a size and amniotic fluid level difference between twins
Dizygotic Twins
2/3 are dizygotic (fraternal)
multiple ova, 2 different sperm = 2 zygotes
2 placentas
2 umbilicals
So each baby has its own space
Monozygotic Twins
1/3 are monozygotic (identical)
single ova, 1 sperm = 1 zygote that will split at the 2 cell stage into 2
1 placenta
2 umbilicals
So the babies are sharing space
PREMATUIRTY
Any infant less than 37 weeks gestation
In most cases the causes of premature labor or premature rupture of the membranes followed by labor is unknown
It is important to differentiate the preterm infant from the growth retarded
Unknown why one pregnancy ends early and another goes to term
Risk factors for premature labor
–Low socioeconomic status
–Prior prem birth
–Multiple gestation
–Underlying illness
–Maternal age
–Uterine or vaginal infections
–Stress
–Lifestyles: smoking
–Fertility enhancement
Signs of Premature Labor
- Contractions that are regular (unlike Braxton-Hicks-fake contractions)
- Discharge
- Pressure or cramping
- Can also be mistaked for BH
- Backache
- Severe cramping
Complications are Associated with prematurity
Infections due to immaturity of the skin and immune response
Jaundice, anemia
Retinopathy of Prematurity [ROP]
Respiratory Distress Syndrome [RDS] due to immaturity of the lung, then BronchopulmonaryDysplasia [BPD]
Inappropriate feeding responses and apneicspells due to immaturity of the CNS
Thermal instability
NEC, liver, and kidney function problems
IVH and neurological deficits due to an immature CNS
Prematurity
Survival Statistics
32 + weeks: 98% survival
31 – 28 weeks: 90% survival, high risk of deficits
26 – 23 weeks: 40 – 80% survival dependent on gestational age and birth weight, 50% of survivors have serious debilitating deficits
Less that 5% of all premature births are in this category, but these babes have the most complications and require the most intensive care
Long term chronic issues with survivors include (cerebral palsy (CP), ventilator dependence and CLD, neurodevelopmental challenges
Treatment of Premature Labour
The best preventive measure against premature labor is good prenatal care
Preterm labor can be stopped in approximately 50% of patients with bed rest and the use of drugs to decrease uterine activity
Tocolytics (also called anti-contraction medications or labor repressants) are medications used to suppress premature labor (from the Greek tokos, childbirth, and lytic, capable of dissolving). They are given when delivery would result in premature birth
Tocolysis
The process of stopping labor is called Tocolysis
Objective
- Stop contractions via tocolyticagents like Magnesium Sulfate, Progesterone, Nitrates, and Salbutamol (given via IV)
- Delay infection via antibiotics
- Labor > 40 hours( PROM)
- Encourage lung maturity if labor is not arrested via corticosteroids(Dexamethasoneor Betamethasone) to promote surfactant production and decrease the severity of neonatal respiratory distress
Postmaturity
- Any infant born after 42 weeks gestation is postmature
- The causes of postmaturity are generally unknown
- Infants will have loose hanging skin on the extremities which can be dry and peeling – caused by decreasing amniotic fluid levels and efficiency of the placenta
- Placental insufficiency can lead to asphyxia of the fetus during labor
- Postmature infants are at higher risk for meconium aspiration syndrome (because of the spinctertone they can poop in utero) and hypoglycemia (gestational diabetes)
