CPM Certified Professional Midwife

Answer: B - Postmaturity

This is a case of oligohydramnios due to postmaturity. Postmaturity refers to delivery at past the expected date (at more than 9 months of pregnancy). Oligohydramnios is a condition in which the amniotic fluid is less than normal. By approximately the 36^th week of pregnancy, the normal amount of amniotic fluid is between 800-1000 ml (or 1.4-1.6 pints)-and it gradually begins to reduce until birth. Oligohyramnios is suspected if an AFI shows a fluid level of less than 5 centimeters (or less than the 5th percentile); the absence of a fluid pocket 2-3 cm in depth; or a fluid volume of less than 500mL at 32-36 weeks gestation.

Causes of oligohydramnios include:
1. Fetal chromosomal anomalies
2. Rupture of the membrane
3. Intrauterine infection
4. Postmaturity