The Effect of Supraphysiological Estradiol on Pregnancy Outcomes Differs Between Women With PCOS and Ovulatory Women

Context: Supraphysiological estradiol exposure after ovarian stimulation may disrupt embryo implantation after fresh embryo transfer. Women with polycystic ovary syndrome (PCOS), who usually overrespond to ovarian stimulation, have a better live birth rate after frozen embryo transfer (FET) than after fresh embryo transfer; however, ovulatory women do not.Objective: To evaluate whether the discrepancy in live birth rate after fresh embryo transfer vs FET between these two populations is due to the variation in ovarian response (i.e., peak estradiol level or oocyte number).Design, Setting, Patients, Intervention(s), and Main Outcome Measure(s): This was a secondary analysis of data from two multicenter randomized trials with similar study designs. A total of 1508 women with PCOS and 2157 ovulatory women were randomly assigned to undergo fresh or FET. The primary outcome was live birth.Results: Compared with fresh embryo transfer, FET resulted in a higher live birth rate (51.9% vs 40.7%; OR, 1.57; 95% CI, 1.22 to 2.03) in PCOS women with peak estradiol level. 3000pg/mL but not in those with estradiol level = 16 oocytes, FET yielded a higher live birth rate (54.8% vs 42.1%; OR, 1.67; 95% CI, 1.20 to 2.31), but this was not seen in those with,16 oocytes. In ovulatory women, pregnancy outcomes were similar after fresh embryo transfer and FET in all subgroups.Conclusions: Supraphysiological estradiol after ovarian stimulation may adversely affect pregnancy outcomes in women with PCOS but not in ovulatory women.

背景：卵巢刺激后超生理水平的雌二醇暴露可能会干扰新鲜胚胎移植后的胚胎着床。多囊卵巢综合征（PCOS）女性通常对卵巢刺激反应过度，其冷冻胚胎移植（FET）后的活产率高于新鲜胚胎移植；然而，排卵正常的女性并非如此。 目的：评估这两个人群新鲜胚胎移植与FET后活产率的差异是否是由于卵巢反应的差异（即雌二醇峰值水平或卵母细胞数量）所致。 设计、地点、患者、干预措施及主要观察指标：这是对两项研究设计相似的多中心随机试验数据的二次分析。共有1508名PCOS女性和2157名排卵正常的女性被随机分配接受新鲜胚胎移植或FET。主要结局是活产。 结果：在雌二醇峰值水平≥3000 pg/mL的PCOS女性中，与新鲜胚胎移植相比，FET的活产率更高（51.9%对40.7%；比值比为1.57；95%置信区间为1.22 - 2.03），但在雌二醇水平＜3000 pg/mL的女性中未观察到这种差异。在卵母细胞数量≥16个的PCOS女性中，FET的活产率更高（54.8%对42.1%；比值比为1.67；95%置信区间为1.20 - 2.31），但在卵母细胞数量＜16个的女性中未观察到这种情况。在排卵正常的女性中，所有亚组中新鲜胚胎移植和FET后的妊娠结局相似。 结论：卵巢刺激后的超生理水平的雌二醇可能对PCOS女性的妊娠结局产生不利影响，但对排卵正常的女性无此影响。