Our purpose was to evaluate the pathologic features and outcome of pregnancies that were complicated with adnexal masses and were managed surgically. A review of patients who had persistent adnexal masses during pregnancy and needed surgical removal of tumours was performed from January 1998 to April 2001. There were 14 cases of persistent adnexal masses identified among 2000 deliveries. There were 13 patients who had surgical interventions: nine (69.2%) had surgery during ongoing pregnancy (at mean gestational age 17+/-3.7 weeks), two (15.3%) with caesarean section, one (7.6%) after evacuation of missed abortion and one (7.5%) after delivery. Out of 13, ten (76.9%) were benign [mature cystic teratoma, six (46.9%); serous cyst adenoma, two (15.3%); mucinous cyst adenoma, one (7.6%); paratubal cyst, one (7.6%)] and three (23%) were malignant (one immature teratoma, one papillary cyst adenocarcinoma and one krukenberg tumour]. Both patients operated on after 24 weeks had pre-term delivery. The worst outcome in the form of PPROM and preterm delivery at 28 weeks occurred in a patient who underwent emergency surgery. The incidence of malignancy was four- to fivefold greater in our series than reported in the literature. Ultrasound was unable to distinguish malignant cases. Pregnancy outcome was poorer if surgical intervention was done after >24 weeks and that, too, was done as emergency surgery.