Obstetric Outcomes Subsequent to Intrauterine Death in the First Pregnancy

Abstract

This retrospective cohort study compared obstetrical outcomes in the pregnancy following an intrauterine death with those following a live birth in the first pregnancy in Scottish women having their first and second deliveries in the years 1976 to 2006. A total of 364 women having an intrauterine death in their first pregnancy constituted the cohort. The nonexposed cohort, with an initial live birth, totaled 33,715 women. Ages were comparable in the 2 groups, but the stillbirth group had a higher median body mass index and were less likely than the unexposed group to be married or cohabiting. Exposed women were much likelier than those in the comparison group to be smokers. Exposed women were at an increased risk of both preeclampsia (adjusted odds ratio [OR], 3.1; 95% confidence interval [CI], 1.7-5.7) and placental abruption (adjusted OR, 9.4; 95% CI, 4.5-19.7). Induction of labor and instrumental delivery both were more frequent in exposed women, as were elective and emergency cesarean deliveries. For elective cesarean delivery the OR was 3.1, and the 95% CI was 2-4.8. Malpresentation, prematurity (birth at less than 37 weeks' gestation), and low birth weight all were more likely in the exposed cohort. The adjusted OR for stillbirth was 1.2, with a 95% CI of 0.4-3.4. Although stillbirths occurred in 1.4% of the exposed group and 0.5% of the comparison group, the difference was not statistically significant when adjusted for confounding factors. These findings indicate that intrauterine fetal death increases the risk of obstetrical and perinatal complications in a subsequent pregnancy. In the absence of known risk factors, however, the risk of a second stillbirth is not significantly increased.