O-062 New strategies in ovarian stimulation

Abstract Controlled Ovarian stimulation (COH) has an objective to induce multiple ovulations in order to yield a multiple oocyte harvest and offer multiple embryos available for transfer thereby increasing the efficacy of ART. The theory of a multicyclic development of follicles during the menstrual cycle has prompted new approaches to ovarian stimulation. Research has suggested that recruitable antral follicles are continuously present in the ovaries during the menstrual cycle, and ultrasonographic studies have demonstrated that multiple cohorts or ‘waves’ of 2–5 mm follicles are recruited continuously during a menstrual cycle. Because of the asynchrony between endometrial receptivity and embryo development with a ‘non-conventional start’ stimulation, all the embryos are generally cryopreserved and transferred subsequently. This deferred transfer policy is currently possible given the advances in vitrification techniques, with success rates comparable to those following transfer with ‘fresh’ embryos. New stimulation approaches, together with advanced cryopreservation techniques, allow for a total ‘disarticulation’ between the time of the menstrual cycle, ovarian stimulation start and embryo transfer. This new approach to ovarian stimulation is particularly useful for women seeking fertility preservation, especially where a shortened time to starting cancer treatment is desirable. Also, poor responders could benefit from the new stimulation protocols by continuing ovarian stimulation after the first oocyte retrieval, thereby obtaining more oocytes or embryos compared with the conventional approach. In the quest to reduce the incidence of OHSS and make the clinic OHSS free various antagonist protocols are now routinely used. These and other new protocols discussed will include Late initiation of stimulation, long acting antagonist. Individualised (iCOS) to include mild stimulation, random start, Dual stimulation and double trigger are done to improve efficacy and success rates in certain group of patients. New drugs like Long acting FSH and oral antagonist with their results will be presented. Pre-Treatment medications like Estrogens, Progestogens, Combined CoC, antagonist will also be discussed.