Impact Of Premature LH Surge On Cycle Outcome Of GnRH Antagonist Protocol And Selection Of Treatment Methods

Objectives:This study aimed to explore the impact of premature LH surge on the pregnancy outcome of GnRH antagonist protocol cycle,clarify the predisposing factors of premature LH surge and effective "rescue" measures for premature LH surge cycle.Methods:A retrospective analysis of IVF/ICSI cycles performed with the GnRH antagonist protocol between January 2015 and December 2021 at the Reproductive Medicine Center of the First Affiliated Hospital of Hainan Medical University was conducted.A total of 162 cycles with LH surge≥10IU/L when the follicle diameter was between 12～18mm were selected as the premature LH surge group,and a control group was randomly selected at a ratio of 1:1 according to the screening criteria.The study compared the differences in hormone levels,number of retrieved oocytes,number of embryos,and pregnancy outcomes between the two groups.The logistic regression model speculated the related factors of premature LH surge.In the premature LH surge group,the study also evaluated the effectiveness of two treatment methods:the premature triggering and the increased dosage of the GnRH antagonist.Results:1.Compared with the control group,the premature LH surge group exhibited lower numbers of retrieved oocytes,metaphase Ⅱ(MⅡ)oocytes,transplantable embryos,high-quality embryos,and fresh embryo pregnancy rates;2.The timing of initial antagonist use and basal LH level were identified as independent influencing factors for the occurrence of premature LH surge;3.In the premature LH surge group,there was no significant difference in pregnancy outcomes between subgroups with LH levels of 10-15 IU/L and LH levels≥15 IU/L;4.The number of retrieved oocytes and MⅡ oocytes was significantly higher in the antagonist dose-increase group than in the premature triggering group.However,there was no significant difference in the final pregnancy outcome between these two groups.Conclusions:The premature LH surge can potentially impact the growth and development of ovarian follicles as well as fresh embryo pregnancy rates in GnRH antagonist protocol cycles.Independent risk factors for premature LH surge include delayed initiation of antagonist use and elevated basal LH level.Further,increasing the antagonist dosage after premature LH surge may result in the retrieval of more oocytes than the premature triggering.