MFM

Question 1

What is maternal periarteritis nodosa affecting renal function

Answer 1

It is a complication of malignant hypertension impacting the neonate and associated w/ maternal demise - consider early therapetuic termination.

Question 2

advanced paternal age

Answer 2

higher risk of AD conditions, achondroplasia and marfans

Question 3

What are risks of VBAC? What causes higher success rate in VBAC?

Answer 3

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.

Question 4

what is a major risk factor for transmission of maternal syphillis

Answer 4

inadequate maternal treatment is major risk factor (70-100% risk of transmission)

Question 5

Which prenatal tests are available when?

Answer 5

CVS: 1st trimester, 10-11 weeks

Amniocentesis: 2nd trimester, 12-15 weeks

Cell Free DNA / Non-Invasive Prenatal Sampling: 1st trimester (10 weeks)

Question 6

what causes maternal PIH and what is the cure?

Answer 6

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.

Question 7

maternal cardiac changes

Answer 7

• decrease in BP
• decrease in PVR
• increase in volume
• Increase in CO (SV increases early in pregnancy, HR increases later).

Question 8

which maternal anesthetic medications affect the fetus:

midazolam, diazepam, succinylcholine, thiopental (barbituate), nitrous oxide, isoflurane, morphine

Answer 8

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

Question 9

twinning probabilities and impact of time of zygote splitting

Answer 9

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

Question 10

which population and how frequently does TTTS occur in

Answer 10

occurs in 30% of mono-di (monozygotic) pregnancies.

Question 11

what is ‘fetus papyraceus’

Answer 11

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.

Question 12

what is TRAP (twin reversal arterial perfusion)

Answer 12

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.

Question 13

What is the variability of monozygocity vs dizygocity twinning.

Answer 13

Monozygosity twinning is the same across ivf vs spontaneous pregnancies and same across geographic regions. Dizygocity greatly varies.

Question 14

What is subfertility?

Answer 14

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.

Question 15

What are the different stages of maternal syphillis.

Answer 15

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.

Question 16

What are fetal effects of maternal syphillis?

Answer 16

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).

Question 18

Which biomarker is best at indicated premature delivery.

Answer 18

Fetal fibronectin is most accurate at predicting premature delivery within 7 days of spontaneous.

Sensitive if <3cm dilated, uterine contractions and intact membranes.

Question 19

what are the components of the BPP and what do the scores mean?

Answer 19

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.

Question 20

When is fetal testing indicated for concern for Rh incompatibility?

Answer 20

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.

Question 21

what is the dose of rhogam?

Answer 21

normally one vial (300 ug) at 28 weeks and after delivery if baby is Rh (+). If FMH, then x baby volume/30ml +1 vial.

Question 22

how do you diagnose DDH?

Answer 22

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.

Question 23

what are the adverse effects of various tocolytics

Answer 23

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

Question 24

what is first trimester screening called and what does it include?

Answer 24

combined screening

NT (for CHD and aneupolidy), age, and papp-a + bhcg

85% sensitivity

Question 25

what is second trimester screening called and what does it include?

Answer 25

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

Question 26

what is the integrated screen?

Answer 26

95% senstiivity, done at 18 weeks. includes combined screen (NT+age+papp a + bhcg) + quad screen (afp, hcg, estriol, inhibin)

Question 27

what is a concerning finding on MCA doppler?

Answer 27

peak systolic velocity (PSV) > 1.5 MoM is concerning for significant anemia

Question 28

what is concerned oligo? what is poly?

Answer 28

oligo: AFI <5cm, GVP < 2cm
poly: AFI > 25cm, GVP > 8cm

(mod if AFI > 30, severe if AFI > 40)

Question 29

maternal smoking is associated with what positive and negative side effects to fetus?

Answer 29

(+) decreased preE

(-) placenta previa/abruption/PPROM, IUGR, still birth,

Question 30

what are mechanisms of amniotic fluid clearance?

Answer 30

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)

Question 31

what is maternal ssri assoc with

Answer 31

fetal phtn

Question 32

what is maternal phenytoin assc with

Answer 32

fetal hydantoin syndrome: midface hypoplasia, hyperterolism, FGR

Question 33

what is maternal valproic acid use assc with

Answer 33

NTD and dvpt delay

Question 34

what is the rate of eos gbs? los gbs?

Answer 34

down from 2 to 0.2 /1000. 0.5/1000

Question 35

which type of anesthesia in csection most impacts the neonate?

Answer 35

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

Question 36

when do you test for GDM?

Answer 36

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