Effect of Recombinant FSH Dosing Following Cori-follitropin Alfa in Patients Undergoing in Vitro Fertilization/Intra-citoplasmatic Sperm Injection: a Randomized Controlled Dose-finding Study.

On day 2 or on day 3 of the cycle, blood sampling for estradiol (E2), progesterone (P), follicle stimulating hormone (FSH), luteinising hormone (LH) and human chorionic gonadotropin (hCG) levels, will be per-formed prior to the administration of corifollitropin alfa.

All the blood samples taken during the stimulation for the hormonal profile, starting from day 2, will be performed in a double tube, one for a central assessment and one for the local assessment in order to be used during the monitoring of the cycle. AMH will also be assess on day 2 of the stimulation with a blood sample that will be sent for central assessment.

Administration of the GnRH antagonist ganirelix (Orgalutran®, MSD) will be initiated on day 6 of stimula-tion in all treatment arms at a daily dose of 0.25 mg to prevent a premature LH surge. Suppression with the GnRH antagonist will be continued until the day of final oocyte maturation. Endocrine monitoring and ultrasound scan will be carried out on day 8 of stimulation and repeated every two days until trigger, de-pending on the patients' response. Triggering for final oocyte maturation is performed as soon as 3 follicles of ≥17 mm will be observed.

Cycles will be cancelled if less than 3 follicles of 12 mm are observed on day 8 day of stimulation, nonethe-less, blood test for hormonal evaluation will be performed in any case on day 8.

Oocyte maturation will be triggered with a single subcutaneous injection of hCG (Pregnyl®: 5000UI/sc, MSD, or 10000UI/sc if body weight exceeds 80 kg) as soon as 3 follicles of ≥17 mm will be observed. Ap-proximately 34-36 hours after trigger, oocyte retrieval will be performed. An embryo transfer will be per-formed on day 3 or on day 5 of embryonic development; one or 2 embryos will be replaced.