Elevated luteinizing hormone levels during the artificial endometrial preparation cycle do not impact pregnancy outcomes in patients undergoing single vitrified-warmed blastocyst transfer

The effect of an increase in luteinizing hormone levels on pregnancy outcomes in patients undergoing artificial endometrial preparation for frozen embryo transfer has not been definitively elucidated. We aimed to investigate the effect of elevated luteinizing hormone levels, measured prior to progesterone administration, on the ongoing pregnancy rate in patients undergoing artificial endometrial preparation for single vitrified-warmed blastocyst transfer. Patients began taking oral oestradiol valerate on menstrual day 2-3. When the endometrial thickness reached ≥7 mm, they were tested for oestradiol, progesterone, and luteinizing hormone, and luteal phase support was started. The participants were divided into four groups based on luteinizing hormone percentiles, and differences in pregnancy outcomes were examined. No significant differences were observed for on-going pregnancy rate and the other pregnancy outcomes between the groups. In multivariate logistic regression analysis, not the luteinizing hormone levels but the quality of embryo had a significant influence on ongoing pregnancy (<i>p</i> = 0.004; adjusted odds ratio, 1.8; 95% confidence interval, 1.213-2.675). The elevation of luteinizing hormone levels during artificial endometrial preparation did not have an impact on the ongoing pregnancy or the other pregnancy outcomes.