Second trimester dilation and evacuation: a risk factor for preterm birth?

OBJECTIVE: To evaluate whether second trimester pregnancy termination with dilation and evacuation (D&E) vs induction of labor (IOL) affects subsequent risk of preterm birth. STUDY DESIGN: Our cohort was a retrospective cohort of women undergoing second trimester pregnancy termination for fetal anomalies, fetal death or previable premature rupture of membranes. We analyzed the rates of spontaneous delivery <37 weeks in the first pregnancy following the termination. We also compared preterm birth rates in our cohort with national averages and analyzed by the total number of prior procedures. RESULT: There were 173 women in our cohort. Women who had undergone a D&E (n=130) were less likely to have a subsequent preterm birth (6.9 vs 30.2%; P < 0.01). This held true for a low risk subset without obstetric risk factors. There was no statistical difference in preterm birth rates for women who had undergone a D&E as compared with national averages, nor between the rates of preterm birth for women with 0, 1, 2 or 3 or more prior first or second trimester procedures. CONCLUSION: We did not find that D&E was a risk factor for preterm delivery when compared with women with a prior IOL or national rates.