Is induced abortion with misoprostol a risk factor for late abortion or preterm delivery in subsequent pregnancies?
OBJECTIVE: To examine whether a first or second trimester induced abortion with misoprostol influences the risk of late abortion or preterm delivery in subsequent pregnancies. STUDY DESIGN: Case-control study in a teaching hospital from January 2005 to June 2006. The cases had singleton pregnancies delivered at 16-36 weeks of gestation after spontaneous late abortions, preterm labor or preterm premature rupture of membrane, or induction of labor for preterm premature rupture of membrane before 37 weeks. The control group was composed of the two consecutive spontaneous singleton deliveries at >or=37 weeks of gestation after each new case (ratio 2/1). The principal outcome measure was late abortion or preterm delivery. The association between late abortion or preterm delivery and a previous induced abortion with misoprostol was first assessed with the Cochran-Mantel-Haenszel chi-square test. Conditional logistic regression models adapted for clustered data were then further used to quant