Obstetric outcomes in women with sonographically identified uterine leiomyomata.

Objective: To examine the association between leiomyomata and complications during pregnancy, delivery, and the puerperium.

Methods: We conducted a retrospective cohort study comparing pregnancy outcomes in women with and without uterine leiomyomata who underwent routine second trimester obstetric ultrasonography and delivered viable infants at a single institution. Potential confounding variables, including maternal age, weight, ethnicity, parity, gestational age, epidural use, and labor induction, were controlled for using multivariate logistic regression techniques.

Results: From 1993 to 2003, 15,104 women underwent routine second trimester prenatal ultrasonography, and 401 (2.7%) women were identified with at least 1 leiomyoma. By univariate and multivariate analyses, the presence of leiomyomata was associated with increased risks for cesarean delivery (adjusted odds ratio [AOR] 1.57, 95% confidence interval [CI] 1.16-2.13), breech presentation (AOR 1.64, 95% CI 1.11-2.40), malposition (AOR 1.59, 95% CI 1.18-2.15), preterm delivery (AOR 1.45, 95% CI 1.08-1.96), placenta previa (AOR 1.86, 95% CI 1.02-3.39), and severe postpartum hemorrhage (AOR 2.57, 95% CI 1.54-4.27). Premature rupture of membranes, operative vaginal delivery, chorioamnionitis, and endomyometritis were not associated with leiomyomata. Median length of labor was not different between the 2 groups. When compared with leiomyomata less than 10 cm in size, leiomyomata 10 cm or larger were associated with rates of cesarean delivery that were not statistically different (25% compared with 31%, P = .49).

Conclusion: Pregnant women with leiomyomata are at increased risk for cesarean delivery, breech presentation, malposition, preterm delivery, placenta previa, and severe post partum hemorrhage. Women with leiomyomata 10 cm or larger achieve a vaginal delivery rate of nearly 70%. These results are useful for preconception and prenatal counseling of women with leiomyomata.

Level Of Evidence: II-2.