MFM Flashcards
What is maternal periarteritis nodosa affecting renal function
It is a complication of malignant hypertension impacting the neonate and associated w/ maternal demise - consider early therapetuic termination.
advanced paternal age
higher risk of AD conditions, achondroplasia and marfans
What are risks of VBAC? What causes higher success rate in VBAC?
Higher risk of HIE/death/stillbirth, higher risk of uterine rupture, higher risk if augmented labor.
Better chance of success if prior VBAC or NSVD.
what is a major risk factor for transmission of maternal syphillis
inadequate maternal treatment is major risk factor (70-100% risk of transmission)
Which prenatal tests are available when?
CVS: 1st trimester, 10-11 weeks
Amniocentesis: 2nd trimester, 12-15 weeks
Cell Free DNA / Non-Invasive Prenatal Sampling: 1st trimester (10 weeks)
what causes maternal PIH and what is the cure?
decreased amounts of PIGF (placental growth factor) –> enothelial dysfunction –> proteinuria/htn. severity of pih correlates with urinary pigf reduction
only cure is delivery of placenta.
maternal cardiac changes
- decrease in BP
- decrease in PVR
- increase in volume
- Increase in CO (SV increases early in pregnancy, HR increases later).
which maternal anesthetic medications affect the fetus:
midazolam, diazepam, succinylcholine, thiopental (barbituate), nitrous oxide, isoflurane, morphine
Meds will more likely cross placenta if lipophilic, non0ionized and not protein bound. The UV (umbilical vein): MV (maternal vein) ratio <1 means less likely to impact fetus.
- midazolam and succinylcholine, do not cross over
- diazepam, crosses over very fast.
- thiopental, crosses over but binds to fetal albumin, doesn’t impact fetus
- nitrous oxide and isoflurane - cross over but only impact if prolonged exposure (15 min and 8 min respectively)
- morphine - pretty high uv:mv ration
twinning probabilities and impact of time of zygote splitting
in monozygotic twins: di-di if zygote splits at 0-3d, mono-di if splits at 4-7d, mono-mono if splits at 8-14d, conjoined if splits after 14d
which population and how frequently does TTTS occur in
occurs in 30% of mono-di (monozygotic) pregnancies.
what is ‘fetus papyraceus’
Aka membranous twin, fetus compresus.
Twin demise with absorption of fluid and demised twin becomes a part of amniotic membrane. Occurs in both mono and dizyogtic pregnancies. Surviving twin associated with with cutis aplasia.
what is TRAP (twin reversal arterial perfusion)
Aka acardiac anomaly.
Arterial-arterial connection causes healthy twin to pump blood to twin with dysfunctional heart. Selective perfusion to lower extremties so recipient usually acephalic and hypoplastic upper extremities.
Only happens in mono-mono twins.
What is the variability of monozygocity vs dizygocity twinning.
Monozygosity twinning is the same across ivf vs spontaneous pregnancies and same across geographic regions. Dizygocity greatly varies.
What is subfertility?
Mothers who get pregnant without IVF/ART after trying for >1 year are considered ‘subfertile’. These fetuses are more likely to have perinatal demise and maternal/fetal complications.
What are the different stages of maternal syphillis.
Infants are most affected by stage of maternal disease.
Primary disease: papule –> chancre.
Secondary:systemic rash, lymphadenopathy, alopecia, neurologic.
Latent: asymptomatic.
Increasing risk of transmission : 1 > 2 > early latent > late latent.
What are fetal effects of maternal syphillis?
If mild: fetal effects are inflammatory and impacting immune system.
If severe: fever, irritability, FTT, snuffles, cutaneous rashes. Can be born in shock/dic/HSM (may worsen with PCN).
Which biomarker is best at indicated premature delivery.
Fetal fibronectin is most accurate at predicting premature delivery within 7 days of spontaneous.
Sensitive if <3cm dilated, uterine contractions and intact membranes.
what are the components of the BPP and what do the scores mean?
Score out of 10, five components:
NST: heart rate reactivity x2 in 20 minutes. 40 minutes if asleep.
AF: pockets >2cm of volume
Movement: 4 limb movements in 30 minutes
Tone: Flexion/extension of extremities
Breathing: rhythmic diaphragm contraction x30 sec
0-4 –> deliver. 6 –> repeat in 6-24h. 8-10 –> reassuring.
When is fetal testing indicated for concern for Rh incompatibility?
If maternal titers are 1:64 or greater. This means that when serum is diluted x64, Ab is still detectable. Doppler is the most benign way to assess neonate.
what is the dose of rhogam?
normally one vial (300 ug) at 28 weeks and after delivery if baby is Rh (+). If FMH, then x baby volume/30ml +1 vial.
how do you diagnose DDH?
Ortalani is most significant finding. RF = female, breech*, family history*. Most resolve by 2-6 weeks. F/u with US at 4w if still concerning. In high risk asymptomatic, evaluate at 6w-4m. Goal is to diagnose by 6m. Refer to ortho if concern.
what are the adverse effects of various tocolytics
nifedipine (ca channel blocker) - good tocolytic, mininmal consequence to fetus, infact assc with good neonatal outcomes.
terbutaline (b sympathomimetic) - acts on b2 uterine smooth muscle to relax. okay tocolytic, fetal tachycardia, hydrops/still birth, hyoglycemia (after initial hyperglycemia/hyperinsulinism b/c of increased glycogen break down in liver)
indomethacin: inhibit conversion of arachadonic acid to progtoglandin. can causes narrowing of PDA after 32 w and oligo due to renal artery stenosis. Linked to adverse neonatal outcomes.
magnesium: inhibits ACh releat at NMF. fetal apnea, hypotonia
what is first trimester screening called and what does it include?
combined screening
NT (for CHD and aneupolidy), age, and papp-a + bhcg
85% sensitivity
what is second trimester screening called and what does it include?
quad screen
afp, estriol, hcg, inhibin (not in triple screen, no one uses triple screen anymore)
afp is decreased in aneuploidy, increased when skin barrier is compromised, twins and iugr. most common reason it is wrong is inaccurate EGA
what is the integrated screen?
95% senstiivity, done at 18 weeks. includes combined screen (NT+age+papp a + bhcg) + quad screen (afp, hcg, estriol, inhibin)
what is a concerning finding on MCA doppler?
peak systolic velocity (PSV) > 1.5 MoM is concerning for significant anemia
what is concerned oligo? what is poly?
oligo: AFI <5cm, GVP < 2cm
poly: AFI > 25cm, GVP > 8cm
(mod if AFI > 30, severe if AFI > 40)
maternal smoking is associated with what positive and negative side effects to fetus?
(+) decreased preE
(-) placenta previa/abruption/PPROM, IUGR, still birth,
what are mechanisms of amniotic fluid clearance?
1) swallowing (upto 1/2 - 1 L in term)
2) intramembranous absorption through fetal vessels on placenta (200-500mL)
3) TRANSmembranous absorption (AF to maternal vessels) is small (10mL)
what is maternal ssri assoc with
fetal phtn
what is maternal phenytoin assc with
fetal hydantoin syndrome: midface hypoplasia, hyperterolism, FGR
what is maternal valproic acid use assc with
NTD and dvpt delay
what is the rate of eos gbs? los gbs?
down from 2 to 0.2 /1000. 0.5/1000
which type of anesthesia in csection most impacts the neonate?
induction anesthesia: will be metabolized in 10 minutes, does cross over the placenta
NM blockade: Does not cross over
maintenance anesthesia: does cross over and does impact the fetus the most. Will usually clear with some good ventilation
when do you test for GDM?
low risk –> don’t need to
med risk –> (ethnicity w/ high prevalance) –> 24-28w : either 2 step test (50g glu –> check in one hour (130-140 wnl) OGTT if abnormal) or 1 step: diagnostic OGTT on everyone (2hr 75g/3h 100g after overnight fasting, then check at the hour. (+) if >180, > 155, > 140)
high risk –> family hx, obesity, loss of prior child –> as early as possible
