OBJECTIVE To determine the optimal endometrial preparation protocols of frozen-thawed embryo transfer (FET) in young women with regular menstrual cycles. DESIGN Retrospective cohort study. SETTING Public fertility center. PATIENT(S) Infertile women with regular menstrual cycles undergoing FET. INTERVENTION(S) Natural cycle (NC) treatment for patients with proven ovulation in previous cycles or who refused medication (n = 308), or hormone treatment (HT) for patients who could not be frequently monitored (n = 1,538). MAIN OUTCOME MEASURE(S) Live-birth rates. RESULT(S) The live-birth rates were 61.73% in the NC group and 55.11% in the HT group. The effect size of the endometrial preparation on live-birth rates was evaluated in prespecified and exploratory subgroups in each subgroup, and multivariable logistic regression analysis was used to determine which variables could be independently associated with the live-birth rate. The HT patients had a lower chance of live birth in all subgroups: endometrial thickness on the day of progesterone administration, triple-line endometrial pattern, female age at embryo transfer, fertilization type, and protocol in the fresh cycle. Multivariable analysis showed NC to be associated with an increased likelihood of live birth compared with HT. CONCLUSION(S) Natural cycle treatment has a higher chance of live birth than HT for endometrial preparation in young women with regular menstrual cycles.

中文翻译：

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与激素替代疗法相比，对月经周期规律的年轻女性进行自然周期冻融胚胎移植可提高活产率：一项回顾性队列研究

目的 确定月经周期规律的年轻女性冻融胚胎移植 (FET) 的最佳子宫内膜制备方案。设计 回顾性队列研究。设置公共生育中心。患者 接受 FET 的月经周期规律的不孕女性。干预(S) 自然周期 (NC) 治疗用于先前周期中证实有排卵或拒绝药物治疗的患者 (n = 308)，或激素治疗 (HT) 用于无法经常监测的患者 (n = 1,538)。主要结果测量活产率。结果 NC 组的活产率为 61.73%，HT 组为 55.11%。在每个亚组的预先指定和探索性亚组中评估子宫内膜准备对活产率的影响大小，多变量逻辑回归分析用于确定哪些变量可以与活产率独立相关。HT 患者在所有亚组中活产的机会较低：孕酮给药当天的子宫内膜厚度、三线子宫内膜模式、胚胎移植时的女性年龄、受精类型和新鲜周期中的方案。多变量分析显示，与 HT 相比，NC 与活产可能性增加有关。结论(S) 对于月经周期规律的年轻女性进行子宫内膜准备，自然周期治疗比 HT 有更高的活产机会。孕酮给药当天的子宫内膜厚度、三线子宫内膜模式、胚胎移植时的女性年龄、受精类型和新鲜周期中的方案。多变量分析表明，与 HT 相比，NC 与活产可能性增加有关。结论(S) 对于月经周期规律的年轻女性进行子宫内膜准备，自然周期治疗比 HT 有更高的活产机会。孕酮给药当天的子宫内膜厚度、三线子宫内膜模式、胚胎移植时的女性年龄、受精类型和新鲜周期中的方案。多变量分析表明，与 HT 相比，NC 与活产可能性增加有关。结论(S) 对于月经周期规律的年轻女性进行子宫内膜准备，自然周期治疗比 HT 有更高的活产机会。