Down-Regulation Ovulation-Induction Leads to Favorable Outcomes in a Single Frozen-Thawed Blastocyst Transfer RCT.

Shi-Bin Chao,Yun Zhou,Qing-Yuan Sun,Wen-Ting Cao,Jian-Chun Li,Yan-Hong Wang

doi:10.3389/fendo.2022.797121

Abstract

ObjectiveElective single embryo transfer (eSET) has been increasingly advocated to achieve the goal of delivering a single healthy baby. A novel endometrial preparation approach down-regulation ovulation-induction (DROI) proposed by our team was demonstrated in an RCT that DROI could significantly improve the reproductive outcome compared with modified natural cycle. We aimed to evaluate whether DROI improved clinic pregnancy rate in this single frozen-thawed blastocyst transfer RCT compared with hormone replace treatment (HRT).MethodEligible participants were recruited and randomized into one of two endometrial preparation regimens: DROI or HRT between March 15, 2019 and March 12, 2021. The primary outcome was clinical pregnancy rate (CPR). The secondary endpoints included ongoing pregnancy rate (OPR), biochemical miscarriage and first trimester pregnancy loss. This trial is registered at the Chinese Clinical Trial Registry, number ChiCTR2000039804.Result (s)A total of 330 women were randomized in a 1:1 ratio between two groups and 289 women received embryo transfer and completed the study (142 DROI; 147HRT). Pregnancy outcomes were significantly different between the two groups. The CPR and OPR in the DROI group were significantly higher than those of the HRT group (64.08% versus 46.94%, P<0.01; 56.34% versus 38.78%,P<0.01). The biochemical miscarriage and first trimester pregnancy loss were comparable between the two groups.Conclusion (s)The findings of this RCT support the suggestion that the DROI might be a more efficient and promising alternative endometrial preparation approach for FET. Moreover, DROI could play a critical role in promoting uptake of single embryo transfer strategies in FET.

Highlights

Due to the well-known advantages of frozen-thawed embryo transfer (FET), such as prevention of ovarian hyperstimulation syndrome (OHSS) and increasing cumulative live birth rates (CLBRs) [1, 2], the proportion and the number of FET cycles performed have increased dramatically in recent years [3]
Inspired by preferable endometrial receptivity of the depot gonadotropin releasing hormone (GnRH)-a COS protocol [16, 17], we proposed the DROI as an endometrial preparation protocol and demonstrated in a pilot RCT that DROI could significantly improve the reproductive outcome of FET compared to modified natural cycle [18]
Remaining patients received treatment according to study group allocation, resulting in 142 patients (49.13%) receiving DROI-FET and 147 (50.87%) receiving HRT-FET

Summary

Introduction

Due to the well-known advantages of frozen-thawed embryo transfer (FET), such as prevention of ovarian hyperstimulation syndrome (OHSS) and increasing cumulative live birth rates (CLBRs) [1, 2], the proportion and the number of FET cycles performed have increased dramatically in recent years [3]. In contrast to the complex COS, FET procedures are simpler, with the primary objective being to adequate preparation of the endometrium to receive the thawed embryo(s). Various endometrial preparation regimens have been developed for FET. There is no consensus on the optimal approach for endometrial preparation [4]. Elective single embryo transfer (eSET) is the most efficient approach to reduce the risk of multiple gestations [7]. Despite strong advocacy for its universal adoption, its widespread uptake is slow because reducing the number of embryos transferred compromise the pregnancy rate [8]. Single blastocyst transfer strategy is recommended [11]

Methods

Results

Conclusion