Intensified ovarian stimulation in a GnRH antagonist protocol with agonist triggering: a prospective, clinical feasibility study.

The threat of severe ovarian hyperstimulation syndrome (OHSS) and the increase in discomfort for the patient has limited the feasibility of maximizing the oocyte yield per treatment cycle. A gonadotrophin-releasing hormone (GnRH) antagonist protocol with agonist triggering and vitrification of all 2PN oocytes can eliminate the risk of OHSS. This prospective, single-centre, cohort study in 30 good-responder IVF patients ≤ 36 years reports the feasibility of arbitrarily intensifying stimulation in a GnRH antagonist protocol in terms of tolerability, safety and efficacy. Ovarian stimulation was performed with 225-375IU FSH, induction of final oocyte maturation with 0.2mg GnRH agonist followed by vitrification of all 2 pronuclear (2PN) oocytes and repetitive vitrified-warmed embryo transfer cycles. Main outcomes were severe OHSS incidence, tolerability, assessed by a questionnaire, and cumulative live birth rate. On average, 17 oocytes were retrieved (range 4-42) and 8.4 oocytes at the 2PN stage were cryopreserved (range 3-22). No case of severe OHSS was observed (0%, 95 CI 0-11.4%). Tolerability was good. The cumulative live birth rate per patient undergoing at least one vitrified-warmed embryo transfer was 26.9% (7/26, 95% CI 13.7-46.1%). This approach can be explored in future larger-sized controlled studies.

Cumulative live birth rates after GnRH-agonist triggering of final oocyte maturation in patients at risk of OHSS: a prospective, clinical cohort study.

OBJECTIVES: To prospectively study the incidence of OHSS, live birth likelihood and neonatal outcome after GnRH-agonist triggering of final oocyte maturation and vitrification of all pronucleate (2PN) oocytes for later frozen-thawed embryo transfer (FRET) in an OHSS-risk population. STUDY DESIGN: Prospective, clinical cohort study (12/2004-5/2009). Forty patients undergoing ovarian stimulation in a GnRH-antagonist protocol and at risk of developing severe OHSS underwent triggering with 0.2mg triptorelin and elective vitrification of all 2PN-oocytes for later frozen-thawed embryo transfer. RESULTS: The incidence of OHSS was 0% (0/40; 95% confidence interval: 0.0-6.4%). Thirty-nine patients underwent 87 FRETs (mean number of FRETs per patient: 2.2+/-1.6; range: 1-7). The cumulative live birth rate per patient was 35.0% (14/40; 95% confidence interval: 23.9-48.0%). Mean time-to-conception resulting in live birth after agonist triggering was 24.2 (+/-17.1; range: 9-67) weeks. Nine healthy singletons and five twins were born. CONCLUSIONS: A treatment algorithm combining agonist trigger with vitrification of all 2PN-oocytes is feasible and safe, and provides patients with a good cumulative chance of live birth.