Low-dose Human Chorionic Gonadotropin Versus Estradiol/progesterone Luteal Phase Support in Gonadotropin-releasing Hormone Agonist-triggered Assisted Reproductive Technique Cycles: Understanding a New Approach

It remains unclear how GnRH agonist (GnRHa) triggering affects the luteal phase, so we investigated the luteal phase after GnRHa triggering, supported with conventional E(2)/P with or without low-dose hCG. E(2)/P support, compared with low-dose hCG, induced a shorter luteal phase (11.2 ± 1.1 vs. 15.0 ± 1.6 days) and fewer subjective complaints (0 vs. 42%), whereas hCG caused more free fluid accumulation and enlarged ovaries than E(2)/P alone. Steroids and low-dose hCG differentially affected corpus luteum function, ovarian size, free fluid accumulation, and patient comfort.