Ectopic Pregnancy in In-Vitro Fertilisation - Embryo Transfer in a Patient with Natural Killer Cell Imbalance and Endometriosis

The incidence of ectopic pregnancy (EP) worldwide is 1–2% of all pregnancies. Endometriosis poses an additional risk for EP; the odds ratio has been reported as 2.66 (95% confidence interval [CI] = 1.14–6.21, p = .02). However, the mechanisms are not fully understood. Natural killer cells (NK cells) have also been proposed to play a role in ectopic implantation. Here we present a case of a 32-year-old female who presented with a history of primary infertility and three failed IVF cycles in the past. The patient had an incidental ovarian endometrioma of 3 × 4 cm and a high level of serum NK cells. Alpha-thymosin therapy for 2 weeks was given in view of recurrent implantation failure. Subsequently, the patient underwent two cycles of frozen embryo transfer. In both the cycles, the patient tested positive. The first resulted in a blighted ovum and the second in ectopic conception. The ectopic conception was managed medically. In this article, we discuss the possible role of ovarian endometrioma and serum NK cells.