Luteinizing hormone (LH) plays an integral role in follicular development. In gonadotropin-releasing hormone (GnRH) antagonist protocols, LH levels have been demonstrated to affect assisted reproductive technology (ART) outcomes. However, the exact nature of this relationship remains unclear, and LH measurements at a single time point may not be sufficient to capture it fully. We conducted a retrospective cohort study on 4,953 infertile women who underwent their first ART cycle with the GnRH antagonist protocol. Four LH measurements (basal status, antagonist administration day and 24 h later, and ovulation trigger day) were obtain for all participants. We used group-based trajectory modeling (GBTM) to characterize the trajectories of LH level changes during antagonist protocol implementation. Factors influencing the different LH trajectories were explored. Associations between LH levels at different time points and their trajectories with the number of obtained oocytes and ART outcomes in embryo transfer (ET) cycles were analyzed. Based on the statistical criteria, the model with 4 trajectories were selected as the best-fitting model, and the LH change trajectories during antagonist protocol can be grouped into stable (77.0%), rising (11.0%), decreasing (6.2%) and fluctuating (5.8%) types. Different trajectory groups exhibited significant differences in the number of retrieved oocytes. Compared with that in the stable trajectory group, the oocyte yield in the rising trajectory group decreased and that in the fluctuating trajectory group increased. Of these participants, 884 underwent fresh ET cycles, with no significant differences in pregnancy outcomes between the different trajectory groups. On ovulation trigger day, high LH levels predicted better pregnancy outcomes, indicating significant positive associations with the odds of biochemical pregnancy, clinical pregnancy and live birth. Oocyte yield differed significantly among the LH trajectory groups, suggesting that LH dynamics during antagonist controlled ovarian stimulation may be relevant to treatment outcomes. For individuals with risk factors for a rising trajectory (e.g., advanced age, higher body mass index), closer monitoring of LH profiles may be warranted. For fresh ET cycles, trigger-day LH levels may merit heightened clinical attention.
Su et al. (Sat,) studied this question.