We present a patient with persistent bilateral megalocystic ovaries following in vitro fertilization which was detected during cesarean section. A 24 year-old primigravida presented to our clinic at the 36th week of a twin pregnancy with labour pain and cervical dilatation. On ultrasound examination, 2 masses of 90x60 and 60x70 mm were seen in the right and left adnexal regions respectively. Her history showed that she had unexplained infertility for 4 years and had undergone IVF with gonadotropin releasing hormone (GnRH)-agonist stimulation. Two embryos were transferred. Twin pregnancy was detected on ultrasound examination. The patient was delivered by emergency caesarean section due to transverse presentations at 36th weeks of gestation. During the operation, both adnexae were markedly enlarged, the right ovary measuring about 15x18 cm and the left about 16x18 cm. There was minimal ascites in the abdominal cavity. Ovarian biopsy was performed and the final pathology report showed bilateral follicle cysts. The patient was discharged on the postoperative 4th day. The patient was seen 4 weeks later. She had no complaints and ultrasound follow-up revealed a normal size uterus and ovaries. We should keep in mind that hyperstimulated, enlarged ovaries and its complication may be seen in the late weeks of pregnancy, even at term, in cases of in vitro fertilization cases. Therefore, close follow-up of pregnant IVF patints is recommended whether they had OHSS or not, because ovarian torsion caused by hyperstimulated ovaries may be difficult to diagnose during pregnancy.

Keywords: Bilateral megalocystic ovaries, in vitro fertilization, term pregnancy, OHSS, cesarean delivery