Fetal Development, Maternal adaptation Flashcards
Lifespan of fetal RBCs?
90 days
Kleihauer-Betke test
To test presence of fetal blood cells in maternal circulation
Test to determine presence of fetal hemorrhage - to know how much rhogam to give
At how many weeks AOG is surfactant present?
Starts to appear in amniotic fluid at 28-32 weeks
Most active component of surfactant
Dipalmitoylphosphatidylcholine (DPPC)
Full lung development is achieved at?
8 years of age!
Alveolar development begins just before birth, until 8 yrs old
Peak of HCG?
8-10 weeks AOG
Aka “Pregnancy Hormone”
HCG (Human Chorionic Gonadotropin)
Best known function of HCG
Rescue and maintenance of corpus luteum in early pregnancy until the placenta can take over at 6-8 weeks AOG
Maintains corpus luteum in early pregnancy
HCG
Hormone responsible for formation of male external genitalia?
DHT
In androgen insensitivity, there is a problem with the receptors for DHT so there is no development of external male genitalia
Hormone responsible for development of male internal genitalia?
Testosterone
Other names for HPL?
Other names:
Human Placental Lactogen
Chorionic Growth hormone
Chorionic Somatomammotropin
AOG where HPL is highest? Relevance?
24-28 weeks
HPL is thought to increase maternal insulin resistance that occurs as pregnancy progresses - peak at 24-28 weeks
Hormone with GH-like activity, with anti-insulin action
HPL - “diabetogenic”
Source of progesterone in first 6-7 weeks
Corpus luteum
Where is estriol produced?
Produced almost exclusively by the placental syncitotrophoblast
Most potent estrogen?
Estradiol
What hormone causes the formation of linea nigra?
Melanocyte stimulating factor (MSH)
Black line from above the umbilicus to pubis that may be seen at later part of gestation
Linea nigra
Mask of pregnancy
Chloasma or Melasma gravidarum
BP changes in pregnancy?
No change in systolic BP
Decrease in diastolic BP
- Increased pulse pressure
- Deceased TPR
*Increased CO
GFR in pregnancy? Increase or decrease?
Increases by 50%
Physiologic hydroureter of pregnancy more common in which side?
Right > Left
Physiologic hydroureter of pregnancy due to?
Estrogen: stimulates hypertrophy and muscle elongation
Progesterone: relaxation, generalized atony of urinary tract
Number 1 surgical emergency in pregnancy?
Acute appendicitis
Ptyalism?
Excessive flow of saliva
Effect of progesterone on gallbladder function
Progesterone inhibits CCK - causes GB stasis –> inc incidence of gall stones
All coagulation factors are increased in pregnancy except?
Factor 11 and 13
Pituitary enlargement in pregnancy is secondary to?
Hypertrophy of lactotrophs –> increased susceptibility to hypoxia
Effect of pregnancy to thyroid gland
Hyperplasia of thyroid gland –> because HCG and TSH have similar alpha units
T helper cells in pregnancy - increase or decrease?
Decrease - to accommodate ‘foreign’ baby
Hormone that impairs neutrophil activation
Relaxin - depressed PMN chemotaxis and adherence
WBCs in pregnancy?
Increased numbers of leukocytes
IOP in pregnancy?
Decreases
Increased vitreous outflow
Corneal changes in pregnancy?
Increased corneal thickness due to edema
Decreased corneal sensitivity - slight BOV
Average weight gain in pregnancy?
27.5 lbs
Treatment for asymptomatic bacteriuria?
Nitrofurantoin 100mg BID for 3 days
Or Amoxicillin, First gen cephalosporin
What hormone is responsible for morning sickness?
HCG - nausea, vomiting
Unsafe vaccines in pregnancy
MMR Polio Varicella zoster Yellow fever Small pox
Vitamin A dose not acceptable during pregnancy
> 100,000 IU/ day
Vitamin A is teratogenic
Effect of pregnancy on GI motility
Decreased gastric emptying time
Greater water absorption in intestines –> constipation
Patient presents with pica. What will you request?
CBC with retic count
Pica is associated with IDA - make sure you cure the IDA
Why is there increased complain of headaches in pregnancy?
Due to effect of estrogen
Make sure you rule out pre-eclampsia as cause of headache
Prenatal visit scheduling
Every 4 weeks up to 28 weeks
Every 2 weeks until 36 weeks
Weekly thereafter
Leukorrhea in pregnancy - pathologic or physiogic?
Can be physiologic due to increased vaginal discharge c/o estrogen
Pathologic causes of leukorrhea in pregnancy
Bacterial vaginosis - give metronidazole 500mg BID x 7 days
Trichomoniasis - Metronidazole
Candidiasis - Miconazole, clotrimazole, nystatin
At 20 weeks, uterus expected at what level?
Umbilicus
At 12 weeks, uterus expected at what level?
Pubic symphysis
Uterus palpable at level of umbilicus - corresponds to – weeks AOG?
20 weeks
Uterus palpable at level in between umbilicus and public symphysis - corresponds to – weeks AOG?
16 weeks AOG
Uterus palpable at level of pubic symphysis - corresponds to – weeks AOG?
12 weeks AOG
Discrepancy in fundal size is a difference of – between expected AOG and measurement?
3 cm larger or smaller
Most common cause of false discrepancy in measurement of fundal size
Measurement error
Causes of false discrepancy
Measurement error
Gestational age calculation error
When to do GBS Screening?
35-37 weeks AOG
When to administer Rhogam?
If mom is Rh-, give Rhogam at 24-28 weeks AOG
When to screen for NTDs and other chromosomal anomalies?
16-18 weeks AOG (before 20 weeks)
When to do repeat Hgb and Hct?
28-32 weeks
Blood volume is highest at this point
Hct is diluted
When to give intrapartum GBS prophylaxis?
Previous infant with invasive GBS infection
GBS bacteriuria
Positive GBS screening test (unless CS and no ROM)
Delivery < 37 weeks AOG
Membrane rupture > 18 hrs
Intrapartum temp > 38 C
Intrapartum prophylaxis for GBS
Pen G IV until after delivery
Or ampicillin
If allergic, Erythromycin, Clindamycin
Most common reasons for antepartum testing
Decreased fetal movements DM Post term pregnancy Hypertension IUGR
Normal fetal movements
8-10 kicks every 2 hours (recorded by mother or by tocodynamometer)
MC fetal testing method
Nonstress testing (NST)
Test of fetal condition
Nonstress test (NST)
Test of uteroplacental function
Contraction stress test
Reactive Nonstress test
2 or more accelerations within 20 minutes that peak 15bpm or more above baseline, each lasting 16 seconds or more
MCC of non reactive nonstress test?
Non-hypoxic - Sleeping baby
What to do if Nonreactive nonstress test?
Do vibroacoustic stimulation
If still non-reactive, do contraction stress test or biophysical profile
Interpretation of negative CST
No late decelerations –> reassuring fetal well being
Interpretation of positive CST
Repetitive late decelerations in the presence of 3 uterine contractions in 10 minute period
Components of fetal well being assessed in BPP?
Breathing Movement Muscle tone Amniotic fluid volume Heart rate acceleration - NST
What to do if there’s a presence of Absent or reversed end diastolic flow in umbilical Doppler velocimetry?
Deliver!
You don’t want to see ARED
Indicates uteroplacental insufficiency
MC used measurement in umbilical artery Doppler velocimetry
Umbilical artery systolic-diastolic (SD) ratio
MCC of fetal tachycardia
Maternal fever secondary to chorioamnionitis
MCC of fetal bradycardia
Use of local anesthetics
Minimal variability
<= 5 beats/minute from baselinw
Moderate variability
6-25 beats/ minute from baseline
Normal!
Marked variability
> 25 beats/minute from baseline
Gradual decrease in FHR below baseline beginning and ending with uterine contractions
Early decelerations
Etiology: Head compression
Benign
Abrupt decrease in FHR below baseline of at least 15 bpm with onset to nadir of LESS THAN 30 secs
Variable decelerations
Etiology: umbilical cord compression
Mild to moderate: benign
Severe: reassuring –> fetus may be acidotic
Gradual decrease in FHR below baseline with onset to nadir of at least MORE THAN 30 secs
Late decelerations
Etiology: uteroplacental Insufficiency
Always worrisome!
MC isolated structural defects detected during prenatal diagnosis
Congenital heart defects
Secons MC isolated structural defects detected during prenatal diagnosis
Neural tube defects
When is maternal serum AFP screening done?
14-22 weeks AOG
Results of MSAFP screening?
Reported as multiple of median (MoM)
> 3.5 MoM clearly indicates fetal risk
MCC of increased MSAFP?
AOG dating error
Next step if with increased MSAFP?
Confirm age of gestation
Five cranial signs of NTD
Small BPD
Ventriculomegaly
Lemon sign - frontal bone scalloping
Banana sign - elongation and downward displacement of cerebellum
Effacement/ obliteration of cisterna magnus
Banana sign?
Elongation and downward displacement of cerebellum
Lemon sign?
Frontal bone scalloping
Screening for trisomy 21 during first trimester
Maternal serum B-HCG
Pregnancy-associated plasma protein A (PAPP-A)
UTZ: nuchal translucency
Screening for trisomy 21 during second trimester
ACE-I AFP: low Chorionic gonadotropin: high Estriol: low Inhibin: high
First site of embryonic hematopoeisis?
Yolk sac - 3-8 weeks
