Purpose: To explore four areas of controversy: the benefits of gonadotropin priming, benefits and timing of hCG trigger as well as the ideal protocols for endometrial preparation and luteal support.
Methods: A literature review was performed to explore the current evidence
Results: Current evidence suggests that Gonadotropin priming in combination with hCG prior to collection benefits patients with normal ovaries. In PCOS patients 10,000 IU hCG 38 h before retrieval increases the total number and rate of oocyte maturation. Gonadotropin priming may also benefit PCOS patients. The ideal timing of hCG trigger appears to be when the leading follicle is 10-12 mm. Sparse data exists regarding luteal support protocols.
Conclusions: There is still a need for well-designed studies to establish ideal methods for oocyte priming, timing of retrieval, endometrial preparation and luteal support. Further studies must incorporate both clinical and basic science principles of ovarian, follicular and endometrial physiology.