Comparing the success rate of natural cycle and modified natural cycle protocols for frozen-thawed embryo transfer

Abstract

Objective: The aim of the present study is to compare the effects of Natural Cycle and modified Natural Cycle protocols for frozen-thawed embryo transfer on clinical pregnancy rate and live birth rate. Methods: This prospective randomized controlled trial comprised 145 patients scheduled for frozen-thawed embryo transfer and was conducted at a university hospital between 2019 and 2021. The Natural Cycle protocol was administered to 73 patients and the modified Natural Cycle protocol to 72 patients and the clinical outcome was compared between the groups. The main outcome measure was live birth rate. Results: Baseline characteristics and cycle parameters were similar in both groups. There was no difference in clinical pregnancy rate (58.9% and 54.2%, respectively; p = .565) and live birth rate between the Natural Cycle and modified Natural Cycle groups (49.3% and 48.6% respectively; p = .932). Conclusion: This study established that clinical pregnancy and live birth rates were not affected by natural cycle ovulation being spontaneous or hCG-triggered among patients undergoing frozen-thawed embryo transfer. Thus, the protocol for natural cycle frozen-thawed embryo transfers should be chosen according to the priorities of the patient and the physician.

摘要

目的

本研究的目的是比较自然周期和改良后的自然周期冻融胚胎移植方案对临床妊娠率和活产率的影响。

方法

这项前瞻性的随机对照研究对2019年至2021年在一家大学附属医院纳入145名计划进行冻融胚胎移植的患者。对73名患者实施自然周期方案, 对72名患者实施改良的自然周期方案, 并比较各组的临床结局。主要的结局指标是活产率。

结果

两组的基线特征和周期参数无统计学差异。自然周期组和改良自然周期组的临床妊娠率（分别为58.9%和54.2%；P=0.565）和活产率（分别为49.3%和48.6%；P=0.932）没有差异。

结论

本研究证明了, 在接受冻融胚胎移植的患者中, 临床妊娠率与活产率不受自然周期排卵或hCG诱导排卵的影响。因此, 自然周期冻融胚胎移植的方案应根据患者和医生的优先级来决定。

Keywords:

• Live birth rate
• natural cycle
• modified natural cycle
• clinical pregnancy rate
• endometrium

关键词:

• 活产率
• 自然周期
• 改良自然周期
• 临床妊娠率
• 子宫内膜

Disclosure statement

No potential conflict of interest was reported by the authors.

Funding

The author(s) reported there is no funding associated with the work featured in this article.