Endometrial thickness as a predictor of the reproductive outcomes in fresh and frozen embryo transfer cycles

Abstract

To evaluate the relationship between endometrial thickness during fresh in vitro fertilization (IVF) cycles and the clinical outcomes of subsequent frozen embryo transfer (FET) cycles.FET cycles using at least one morphological good-quality blastocyst conducted between 2012 and 2013 at a university-based reproductive center were reviewed retrospectively. Endometrial ultrasonographic characteristics were recorded both on the oocyte retrieval day and on the day of progesterone supplementation in FET cycles. Clinical pregnancy rate, spontaneous abortion rate, and live birth rate were analyzed.One thousand five hundred twelve FET cycles was included. The results showed that significant difference in endometrial thickness on day of oocyte retrieval (P = .03) was observed between the live birth group (n = 844) and no live birth group (n = 668), while no significant difference in FET endometrial thickness was found (P = .261) between the live birth group and no live birth group. For endometrial thickness on oocyte retrieval day, clinical pregnancy rate ranged from 50.0% among patients with an endometrial thickness of ≤6 mm to 84.2% among patients with an endometrial thickness of >16 mm, with live birth rate from 33.3% to 63.2%. Multiple logistic regression analysis of factors related to live birth indicated endometrial thickness on oocyte retrieval day was associated with improved live birth rate (OR was 1.069, 95% CI: 1.011–1.130, P = .019), while FET endometrial thickness did not contribute significantly to pregnancy outcomes following FET cycles. The ROC curves revealed the cut-off points of endometrial thickness on oocyte retrieval day was 8.75 mm for live birth.Endometrial thickness during fresh IVF cycles was a better predictor of endometrial receptivity in subsequent FET cycles than FET cycle endometrial thickness. For those females with thin endometrium in fresh cycles, additional estradiol stimulation might be helpful for adequate endometrial development.

Back to life from frozen state

“…This difference was statistically significant. This finding was comparable with the previous studies 24,25 .…”

“…The endometrial thickness is routinely assessed prior to the embryo transfer. Different studies have looked at different cut offs of endometrial thickness 24,25 . We compared the success of implantation when the endometrial thickness is less than 8mm and more than 8mm.…”

Major Factors Affecting the Live Birth Rate After Frozen Embryo Transfer Among Young Women

“…El-Toukhy et al (22) found significantly higher implantation and pregnancy rates for women with an endometrial thickness of 9-14 mm than in women with an endometrial thickness of 7-8 mm in exogenous hormone replacement cycles. In contrast, some studies found no correlation between FET cycle endometrial thickness and the LBR after FET (23,24). Our results showed that endometrial thickness was one of the most important major predictive factors of a successful outcome following fresh transfers and FETs.…”

PRP in recurrent implantation failure, hope or hype? A Prospective randomized controlled study

“…The observation suggests that the endometrium is not optimally responding to estrogenic stimulation. From time to time, the underlying cause may not be obvious [26] .…”