ABSTRACT
Background: The use of embryo cryopreservation excludes the possible detrimental effects of ovarian stimulation on the endometrium, and higher reproductive outcomes following this policy have been reported. Moreover, gonadotropin-releasing hormone agonist trigger in gonadotropin-releasing hormone [GnRH] antagonist cycles as a substitute for standard human chorionic gonadotropin trigger, minimizes the risk of ovarian hyperstimulation syndrome [OHSS] in fresh as well as frozen embryo transfer cycles [FET]
Objective: To compare the reproductive outcomes and risk of OHSS in fresh vs frozen embryo transfer in high responder patients, undergoing in vitro fertilization triggered with a bolus of GnRH agonist
Materials and Methods: In this randomized, multi-centre study, 121 women undergoing FET and 119 women undergoing fresh ET were investigated as regards clinical pregnancy as the primary outcome and the chemical pregnancy, live birth, OHSS development, and perinatal data as secondary outcomes
Results: There were no significant differences between FET and fresh groups regarding chemical [46.4% vs. 40.2%, p=0.352], clinical [35.8% vs. 38.3%, p=0.699], and ongoing [30.3% vs. 32.7%, p=0.700] pregnancy rates, also live birth [30.3% vs. 29.9%, p=0.953], perinatal outcomes, and OHSS development [35.6% vs. 42.9%, p=0.337]. No woman developed severe OHSS and no one required admission to hospital
Conclusion: Our findings suggest that GnRHa trigger followed by fresh transfer with modified luteal phase support in terms of a small human chorionic gonadotropin bolus is a good strategy to secure good live birth rates and a low risk of clinically relevant OHSS development in in vitro fertilization patients at risk of OHSS
ABSTRACT
The luteal phase of all stimulated in vitro fertilization/intra-cytoplasmic sperm injection [IVF/ICSI] cycles is disrupted, which makes luteal phase support [LPS] mandatory. The cause of the disruption is thought to be the multifollicular development achieved during ovarian stimulation which results in supraphysiological concentrations of steroids secreted by a high number of corpora lutea during the early luteal phase. This will directly inhibit luteinizing hormone [LH] secretion by the pituitary via negative feedback at the level of the hypothalamic-pituitary axis, leading to a luteal phase defect. With the introduction of the gonadotropin-releasing hormone [GnRH] antagonist protocol, it became feasible to trigger final oocyte maturation and ovulation with a single bolus of GnRH agonist [GnRHa] as an alternative to human chorionic gonadotropin [hCG]. GnRHa triggering presents several advantages, including the reduction in or even elimination of ovarian hyperstimulation syndrome. Despite the potential advantages of GnRHa triggering, previous randomized controlled trials reported a poor clinical outcome with high rates of early pregnancy losses, despite supplementation with a standard LPS in the form of progesterone and estradiol. Following these disappointing results, several studies now report a luteal phase rescue after modifications of the LPS, resulting in a reproductive outcome comparable to that seen after hCG triggering. We herein review luteal phase differences between the natural cycle, hCG trigger and GnRHa trigger and present the most recent data on handling the luteal phase after GnRHa triggering