PREGNANCY OUTCOME IN WOMEN WITH LOW MIDTRIMESTER MATERNAL SERUM UNCONJUGATED ESTRIOL

OBJECTIVE: To determine if unexplained low second-trimester maternal s erum unconjugated estriol (MSuE3) is a useful predictor of complicatio ns of pregnancy.STUDY DESIGN: Between February 1, 1990, and January 3, 1993, 10,492 patients underwent prenatal screening using second-trime ster maternal serum alpha-fetoprotein (MSAFP), maternal serum human ch orionic gonadotropin (MShCG) and MSuE3. One hundred ninety-five patien ts with complete obstetric history/delivery records and with <0.4 mult iples of the median (MoM) second-trimester MSuE3 values were matched w ith 261 controls with complete obstetric history/delivery records and normal second-trimester MSAFP, MSuE3 and MShCG. RESULTS: The relative risk of pregnancy loss, as compared to that in controls, was 3.7 (1.4- 9.1 confidence interval [CI], P<.0001) in patients with 0.2-0.4 MoM MS uE3 and 19.3 (6.1-60.5 CI, P<.0001) in patients with <0.2 MoM MSuE3. A fter exclusion of patients with low and high MSAFP and MShCG, the rela tive risk of pregnancy loss for the remaining patients with low MSuE3 teas 3.3 (1.3-8.5 CI, P<.008). CONCLUSION: The data suggest that patie nts with unexplained low second-trimester MSuE3 have an increased risk of pregnancy loss that may not be associated with a high or low MSAFP , MShCG or higher incidence of pregnancy-induced hypertension, gestati onal diabetes, premature rupture of membranes or premature onset of la bor.