Heterotopic triplet pregnancy complicated with ovarian hyperstimulation syndrome following in vitro fertilization.

Heterotopic pregnancy is a rare event that occurs in less than 1% of pregnancies following in vitro fertilization and embryo transfer, especially when complicated with ovarian hyperstimulation syndrome. We report a case of a 31-year-old woman in the 6th gestational week of pregnancy achieved after in vitro fertilization, who was complaining of acute lower abdominal pain and distension, breathing difficulties and vaginal spotting. Transvaginal ultrasound examination and laboratory tests confirmed the ovarian hyperstimulation syndrome in the presence of two viable gestational sacs. The patient's condition worsened five days later with sudden onset of sharp abdominal pain, nausea and vomiting, along with impaired laboratory test values. Laparoscopy was attempted, but enlarged ovaries and adhesions prevented further procedure, which was then converted to mini-laparotomy. Operative removal of the right tubal pregnancy resulted in uncomplicated course of the intrauterine twin pregnancy and delivery of two healthy neonates by cesarean section at 37 weeks of gestation. Clinicians need to be aware of this rare complication where ovarian hyperstimulation syndrome coexists with heterotopic pregnancy after in vitro fertilization and embryo transfer procedure. Enlarged ovaries may mask accurate ultrasound diagnosis, but timely surgical intervention can prevent fatal consequences and result in normal course and outcome of intrauterine pregnancy.