Omental and peritoneal secondary trophoblastic implantation - an unusual complication after IVF

Omental pregnancy is an uncommon form of abdominal pregnancy; it has never been previously reported after IVF. A 35-year-old patient underwent IVF for tubal factor infertility, The treatment cycle was uneventful, but 3 weeks following embryo transfer the patient was diagnosed with a right tubal ectopic pregnancy on ultrasound. A laparoscopic salpingectomy was performed and the patient was discharged home. Two weeks later, the patient presented with abdominal pain and rising serum beta-human chorionic gonadotrophin (beta-HCG). A repeat laparoscopy showed omental and peritoneal trophoblastic implants. These were excised laparoscopically and confirmed on histology to be trophoblastic tissue. The HCG returned to <3 IU/l, 1 week post-operatively. This case emphasizes the importance of intra-operative care during laparoscopic surgery for ectopic pregnancy and the need for post-operative surveillance of serum beta-HCG. An abdominal pregnancy, though rare, has a seven times higher mortality rate than non-abdominal pregnancies. Early diagnosis and treatment can prevent intra-abdominal haemorrhage, as haemorrhagic shock is the commonest cause of mortality from omental pregnancy.