Lecture 11: Normal Pregnancy: Antepartum Care Flashcards
When should women start folic acid supplementation when planning to conceive; what are recommended doses in someone w/ no hx of NTD vs. hx of previous child w/ NTD?
- Begin at least 1 month before conception
- No hx of NTD, folic acid 0.4 mg
- Hx of previous child w/ NTD ↑ to 4.0 mg
List some of the normal PE findings assoc. w/ pregnancy which may be considered abnormal in a non-preg. pt?
- Systolic murmurs w/ exaggerated splitting and S3
- Palmar erythema + Spider angiomas
- Linea nigra
- Striae gravidarum
- Chadwicks sign
What value of hCG is considered a positive test and is when most urine hCG tests can detect it?
25 IU/L
Gestational sac is seen around how many weeks?
5 weeks when mean hCG is 1500-2000 IU/L
What is Naegels rule for estimating the expcted day of delivery for a lady who is normally cycling every 28 day?
(LMP - 3 months) + 7 days = expected date of delivery
What can be meaured on U/S between 6-11 weeks and can determine due date within 7 days?
Crown Rump Length (CRL)
Based on measurement of uterine size what is indicative of 20 weeks?
20 weeks at the umbilicus
What can be measured on U/S at 12-20 weeks and can determine due date within 10 days?
- Femur length
- Abdominal circumference
- Biparietal diameter
What is considered advanced maternal age when genetic counseling should be offered?
35 y/o +
After how many spontaneous abortions should chromosomal studies (karyotyping) be done on a mother and father?
After 3 or more
What is the most common form of inherited mental retardation?
Fragile X syndrome
What 4 things are included in the first trimester screening for fetal aneuploidy?
- Maternal age
- Fetal nuchal translucency (NT) thickness
- Maternal serum b-hCG
- Pregnancy associated plasma protein-A (PAPP-A)
Which finding of fetal nuchal translucent (NT) thickness is associated with both chromosomal and congenital anomalies?
Increased thickness
Which finding of b-hCG and PAPP-A is associated with down syndrome; measurement of what can increase the detection rate?
- ↑ b-hCG and ↓ PAPP-A assoc. w/ Down’s Syndrome
- Addition of nasal bone assessment (absence of) to nuchal translucency measurement ↑ detection rate
What is included in the quadruple screen for second trimester testing of fetal aneuploidy?
- b-hCG
- Estriol
- Serum AFP
- Inhibin A
When is screening for cell-free fetal DNA done and why is it so hyped?
- At 9-10 weeks, looks for cell free fetal DNA, thought to be derived from apoptosis of trophoblastic cells that have entered maternal circulation
- Detection rates for trisomy and sex chromosome disorders are very high
What does cell-free fetal DNA not test for?
- Does NOT test for open neural fetal defects
- Continue to evaluate for NTD w/ maternal AFP or U/S
Cell-Free fetal DNA screening should only be ordered in high risk patients, list 5 situations.
- Advanced maternal age
- Hx of prior pregnancy w/ a trisomy
- Family hx of chromosomal abnormalities
- Fetal U/S abnormalities suggestive of aneuploidy
- Positive serum screening test including 1st trimester, triple or quad screen
If Cell-Free fetal DNA screen is positive what is next step in confirming results?
- Proceed w/ invasive diagnostic test to confirm results:
- Amniocentesis or chorionic villi sampling
The teratogen, Thalidomide, is associated with what congenital deformity?
Phocomelia
Which risk factor category for medications during pregnancy states that adequate well-controlled studies or observations in pregnant women have demonstrated a risk to fetus; but the benefits of therapy may outweight potential risks?
Category D
When is the most vulnerable stage in terms of effects of teratogens?
Day 17 to day 56 post-conception = organogensis
In general what kind of effect do teratogens have after the 4th month up to the end of gestation?
Usually results in delayed growth of organs and not in a malformation
What is the drug of choice for anxiety and depression during pregnancy?
Fluoxetine
Which anti-coagulant does and which does not cross the placenta?
- Coumadin (D) crosses the placenta –> SAB, IUGR, CNS defects
- Heparin (B) does not cross
The anticonvulsant, Diphenylhydantoin, is a known teratogen which may cause what?
Fetal hydantoin syndrome (FHS)
Which 2 anti-convulsants are associated with spina bifida?
Valproic acid and Carbamazepine
What are the 3 dose dependent effects of radiation exposure to a fetus during the critical period of 2-6 weeks post conception?
- Teratogenesis
- Mutagenesis
- Carcinogenesis
If radiation exposure occurs during the first 2 weeks post-conception what is the response like?
Either all or none = will be lethal or no effect
What is the rule of thumb for how much radiation to mother poses no risk to fetus?
<5 rads of exposure = no risk
What are some recommendations you can give to pregnant woman who is suffering from nausea and vomiting?
- Eat small but frequent meals
- Avoid greasy, fried foods
- Room temperature sodas and saltines
- Accupuncture
- Meds = antihistamines, vit B6, and antiemetics (phenergan, zofran)
What is the cause of frequent heartburn during pregnancy?
Due to relaxation of esophageal sphincter by progesterone
What is the frequency of prenatal office visits throughout the pregnacy?
- Every 4 weeks until 28 weeks
- Every 2 weeks from 28-36 weeks
- Weekly until delivery
The first sensation of fetal movement is known as quickening and occurs on average at how many weeks gestation?
20 weeks
At how many weeks gestation do you obtain fetal survery ultrasound?
20 weeks
What routine screening and management is completed at 28 weeks gestation?
- Screen for gestational diabetes and repeat hemoglobin and Hct
- Rhogam injection to Rh negative pt’s
- Tdap give between 27-36 weeks
At how many weeks gestation is screening for group B strep carriers w/ vaginal culture done?
35 weeks
Around 28 weeks have Mom do kick counting to monitor fetal movment and what is the recommended amount she should feel?
10 movements in 2 hours
What is considered a reactive nonstress test (NST)?
2 accelerations of at least 15 beats above baseline lasting at least 15 seconds during 20 minutes of monitoring = normal
What is done if nonstress test is nonreactive?
Further evaluation is warranted w/ a contraction stress test or biophysical profile
What is a contration stress test (CST) and what is considered a positive test?
- Give oxytocin to establish at least 3 contractions in a 10 min period
- If late decelerations are noted w/ the majority of contractions the test is positive and delivery is warranted!
What are the 5 components of the biophysical profile for assessing fetal well-being?
- Nonstress test (NST)
- Fetal breathing movements
- Fetal movement
- Fetal tone
- Amniotic fluid volume
Which score on a biophysical profile for assessing fetal well-being is reassuring, equivocal, and non-reassuring?
- 8-10 is reassuring
- 6 is equivocal; deliver if pt is at term
- 4 or less is nonreassuring; consider delivery
