Comparison between Agonist trigger with HCG luteal phase supplementation vs HCG trigger with progesterone luteal phase supplementation in Antagonist Controlled hyperstimulation Cycle regarding clinical pregnancy rate

Abstract

Controlled ovarian stimulation (COS) is a key component of modern IVF treatment, as the availability of multiple oocytes for fertilization increases the chance of pregnancy. In the stimulated in vitro fertilization/intra-cytoplasmic sperm injection (IVF/ICSI) cycle, the luteal phase is physiologically abnormal. If un-supplemented, this will result in corpus luteum demise and early pregnancy loss. Therefore, to ensure the reproductive outcome of an assisted reproductive treatment (ART) cycle it is crucial to correct the luteal phase. This can be achieved either by increasing the early luteal LH activity or by supplementing with steroid hormones until the circulating hCG produced by the implanting embryo is sufficiently high to secure the function of the corpus luteum. HCG has been the golden standard for ovulation induction for decades, functioning as a surrogate for the mid-cycle LH surge. hCG binds to and activates the same receptor as LH, the LH/hCG receptor, and, thus, by injecting a single bolus of hCG it is possible to trigger final oocyte maturation and ovulation luteum in order to secure a good reproductive outcome. hCG has a significantly longer half-life than that of endogenous LH and the bolus injected to trigger ovulation can support the corpus luteum for 7-10 days. However, during the early/mid luteal phase the hCG secretion from the embryo to the maternal serum is limited. Thus, the result is a decreased corpus luteum function during the early/mid luteal phase, necessitating luteal phase support (LPS)