Abstract：
Superfetation is a very rare occurrence. In the context of assisted reproduction, it has been reported only as an intrauterine pregnancy after ovarian stimulation and/or embryo transfer in the presence of an undiagnosed ectopic pregnancy. Here we report a case of a 27-year-old anovulatory patient, gravida 1 para 1, who underwent two frozen-thawed single-blastocyst transfers in separate cycles. The patient reported that 12 days after the first transfer, she had menstrual bleeding and stopped her estradiol and progesterone supplementation without undergoing a blood human chorionic gonadotropin (βhCG) test. At her request, a second cycle was immediately initiated, with endometrial thickness measuring 4 mm. Eleven days after the second transfer, the βhCG value was inappropriately high. A right tubal pregnancy corresponding to 8 gestational weeks was diagnosed. Laparoscopy revealed a prominent right tubal pregnancy in addition to a significantly smaller left tubal pregnancy. The discordant tubal pregnancies were confirmed histologically. To our knowledge, superfetation involving a second ectopic pregnancy coexistent with a first, contralateral ectopic pregnancy consequent to consecutive in vitro fertilization procedures has not previously been described in the medical literature. This case emphasizes the importance of routine βhCG testing after every IVF cycle, even if apparently unsuccessful.
摘要：
过度是一种非常罕见的现象。在辅助生殖的背景下，据报道,仅在存在未确诊的异位妊娠的情况下,经卵巢刺激和/或胚胎移植后发生宫内妊娠.这里我们报道一例27岁的无排卵患者,gravida1para1，在不同的周期中进行了两次冻融单囊胚移植。患者报告说，第一次转移后12天，她出现月经出血,在未接受人绒毛膜促性腺激素(βhCG)检测的情况下停止了补充雌二醇和孕酮.在她的要求下,第二个周期立即开始，子宫内膜厚度为4毫米。第二次转移后的11天，βhCG值不适当地高。诊断为对应8孕周的右输卵管妊娠。腹腔镜检查显示，除了明显较小的左输卵管妊娠外，还有明显的右输卵管妊娠。组织学上证实了不一致的输卵管妊娠。据我们所知,涉及第二次异位妊娠与第一次异位妊娠共存的超胎儿，医学文献中以前没有描述过连续体外受精手术后的对侧异位妊娠。这个案例强调了每个IVF周期后常规βhCG测试的重要性，即使显然不成功。
