Fetal Growth Restriction

Question 1

What studies should be done to assess fetal growth restriction?

Answer 1

Umbilical artery Doppler studies weekly (for systolic/diastolic ratio, increased as vascular resistance increases)
Amniotic fluid volume 2x weekly (for oligohydramnios due to decreased fetal blood volume, renal flow and urinary output)
Nonstress test/contraction stress test/biophysical profile 2x weekly (for fetal wellbeing)

Question 2

What does the nonstress test look at?

Answer 2

Fetal heart beat recorded over 20 minutes, looking for accels with fetal movement

2x weekly

Question 3

What does the biophysical profile look at?

Answer 3

US evaluation of fetal movement, fetal tone, amniotic fluid, and breathing

1x weekly

Question 4

What methods accurately confirm gestational age at term?

Answer 4

Fetal heart tone 20 weeks by non-electronic fetoscope or 30 weeks by Doppler
36 weeks since positive serum/urine b-hCG
Crown-rump length at 6-12 weeks supports gestational age of at least 39 weeks
US at 13-20 weeks confirms gestational age of at least 39 weeks

Question 5

Fetal growth restriction predisposes to which diseases as an adult?

Answer 5

Cardiovascular disease, HTN, stroke
Type 2 diabetes, obesity
COPD
Cognitive delay in childhood

Question 6

What is a normal amniotic fluid index?

Answer 6

5-25 cm

Question 7

How can fetal lung maturity be assessed?

Answer 7

Amniocentesis

Question 8

Immediate fetal complications at birth from mother with diabetes

Answer 8

Birth trauma (e.g. shoulder dystocia, brachial plexus injury)
Hypoglycemia
Neonatal jaundice
Neonatal acidosis

Note: Preexisting diabetes poorly controlled is associated with risk of congenital anomalies, but not gestational diabetes

Question 9

What methods exist to estimate fetal weight?

Answer 9

Ultrasound - most helpful in ruling out macrosomia than making the diagnosis (estimates of weight are unreliable in fetuses with macrosomia)
Leopold’s maneuvers (abdominal palpation)
Measurement of fundal height

Question 10

When is fetal growth restriction symmetric vs asymmetric?

Answer 10

1st trimester is symmetric: chromosomal abnormalities or congenital infection

2nd-3rd trimester is asymmetric head-sparing growth lag: uteroplacental insufficiency or maternal malnutrition

Question 11

What should be done for fetal growth restriction management?

Answer 11

Regular NST, weekly BPP
Serial growth US
Serial umbilical artery Doppler sonography