Objective To examine whether a previous caesarean section increases the risk for complications in women undergoing a mid-trimester pregnancy termination by labour induction. Design Retrospective analysis of case records between 1997 and 2002.Setting Fetal Medicine Unit of a large teaching hospital.Population One hundred and eight women with a previous caesarean section (study group) and 216 women without such a history (controls), who underwent a second trimester termination of pregnancy. Methods All the terminations were performed between 17 and 24 weeks of gestation by using 400 Ag of oral administration of misoprostol in combination with 400 Ag of intravaginal misoprostol. The same dose of intravaginal misoprostol was repeated every 6 hours for a maximum of five doses. Main outcome measures Severe haemorrhage requiring blood transfusion, post-abortal infection, retained placenta and uterine rupture. Result Complications occurred in 16 out of 108 women of the study group (15%) and in 26 out of 216 of the controls (12%), with only one ruptured uterus in the control group. Conclusion We found no evidence that a previous caesarean delivery affects the incidence of complications when women with such a history undergo a mid-trimester pregnancy termination with misoprostol.