Bilateral tubal pregnancies after a single-embryo transfer.

Case: To present an extremely rare case of bilateral tubal pregnancies following a single-embryo transfer in a woman with a 4 year history of infertility prior to seeking assisted reproductive technology.

Outcome: A pregnancy resulted from the transfer of an embryo that had been thawed from a frozen blastocyst during a hormone replacement cycle. An ultrasound that was performed at 5 weeks and 5 days of gestation revealed a gestational sac, embryo, and heartbeat in the right fallopian tube and similar signs of a gestational sac in the left fallopian tube. A laparoscopy revealed clear signs of an ectopic pregnancy in the ampulla of the right fallopian tube. Signs of swelling also were seen in the ampulla of the left fallopian tube. As the possibility of bilateral tubal pregnancies could not be ruled out, both fallopian tubes were removed. Pathological tests revealed chorionic villi and trophoblasts in both the left and right fallopian tubes.

Conclusion: All previously reported cases of bilateral tubal pregnancies have been a result of multiple ovulations or multiple-embryo transfer and no case of bilateral tubal pregnancies after a single-embryo transfer has ever been reported. No genetic testing was performed; thus, it cannot be definitively stated that the divided chorionic villi and trophoblasts came from only one embryo.