Abstract
In recent years, the freeze-all strategy has been widely adopted and applied. However, with the exception of age, the factors that affect the outcomes of frozen embryo transfer are still unclear. Therefore, the identification and mitigation of factors that influence the live birth rate after frozen embryo transfer is a good way to increase the “take-home-baby” rate of frozen embryo transfer. The objective of this study was to identify factors affecting the live birth rate after cleavage-stage frozen embryo transfer in young ovulatory women. This was a secondary analysis from a previously published multicenter randomized controlled trial (ChiCTR-IOR-14005406) that was originally designed to compare the live birth rate and perinatal complications after fresh embryo transfer to those after frozen embryo transfer among ovulatory women. This study was carried out using a portion of the data from the original randomized controlled trial, which included 917 young women who underwent cleavage-stage frozen embryo transfer. The 16 clinical candidate variables potentially affecting the live birth rate after frozen embryo transfer were analyzed. Univariable analysis and multivariable analysis were performed to assess the relationship between predictive factors and outcomes, with the aim of identifying independent predictors of live birth after frozen embryo transfer. In this study, the live birth rate was 53.0% (486/917). Three independent predictors were ultimately identified as the main factors affecting the live birth rate of ovulatory young women. Infertility duration [odds ratio (OR): 0.933, 95% confidence interval (CI): 0.876–0.995, p = 0.033], endometrial thickness before frozen embryo transfer (OR: 3.375, 95% CI: 1.556–7.321 p = 0.002), and the number of embryos transferred (OR: 2.653, 95% CI:1.226–5,743, p = 0.013) were the major factors contributing to the live birth rate after cleavage-stage frozen embryo transfer among young women. The cut-off point for infertility duration was 4.5 years, and the cut-off point for endometrial thickness was 0.89 cm. Infertility duration, endometrial thickness and number of embryos transferred might affect the live birth rate after frozen embryo transfer among young women. This result could help inform clinical decisions and counseling to increase the live birth rate after frozen embryo transfer among young women.
Highlights
In 1983, the first successful pregnancy after frozen embryo transfer (FET) was reported, and since FET has become an important procedure for infertility treatment [1, 2]
The purpose of this study was to determine the factors affecting the outcome of FET, increase the live birth rate (LBR), and provide information for clinical decisions and consultations
This study assessed the LBR of 917 FET participants using a portion of the data from a large multicenter randomized controlled trial (RCT)
Summary
In 1983, the first successful pregnancy after frozen embryo transfer (FET) was reported, and since FET has become an important procedure for infertility treatment [1, 2]. Compared with that of fresh embryo transfer, the pregnancy outcome of FET is controversial. To verify the effects of freezing embryos on pregnancy outcomes, many studies have compared the pregnancy outcomes of FET with those of fresh embryo transfer [3,4,5,6]. Several studies have reported no significant difference between the live birth rate (LBR) after FET and that after fresh embryo transfer in ovulatory women [3, 4]. Other studies reported that the LBR after FET was better than that of fresh embryo transfer [5, 6]. The factors that affect the FET outcomes of young women are common concerns among physicians. We chose young patients (age ≤35 years) as the target population to identify the factors affecting the LBR after FET in young women
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
