Is an elevated maternal serum uE₃ MoM value in the second trimester associated with a poor pregnancy outcome?

Abstract

OBJECTIVE: To determine if a maternal serum uE₃ value ≥ 5.00 multiples of the median (MoM) is a useful predictor of a poor pregnancy outcome.

METHODS: Between 11/1/93 & 6/1/99, 78,575 women underwent 2^nd trimester maternal serum screening using alpha fetoprotein (AFP), human chorionic gonadotropin (hCG) and unconjugated estriol (uE₃) levels. After eliminating women who had an increased risk for Down syndrome, open neural tube defects, or Trisomy 18 from the study population, 58 women were identified with an uE₃ value ≥ 5.00 MoM. Of these 58 women, 28 women were of more advanced gestational age and 5 women were found to be carrying a multiple gestation. Of the remaining 25 women, 11 women with a maternal serum uE₃ value a 5.00 MoM had a normal pregnancy and outcome. Four women were lost to follow-up. Ten women were found to have an abnormal outcome. Abnormal outcomes included preterm delivery (≤ 37 weeks gestation) (n=7), fetal demise (n=2), and birth defects noted at delivery (n=1). The 10 women with abnormal outcomes were matched for race, gestation, and date of screening with women who had a normal 2^nd trimester maternal serum screen. A relative risk (RR) for pregnancy complications was determined.

RESULTS: A maternal serum uE₃ value ≥ 5.00 MoM was associated with a poor pregnancy outcome (RR 53.6 [confidence interval 6.2-463] with a p<0.0001).

CONCLUSIONS: Although our sample size is small, maternal serum uE₃ values ≥ 5.00 MoM in the 2^nd trimester appear to be associated with an increased risk for a poor pregnancy outcome. Due to the limited number of cases reported, this association between an uE₃ MoM value ≥ 5.00 and poor pregnancy outcome warrants further investigation.