Luteal Phase-start Ovarian Stimulation With Corifollitropin Alfa

The scope of the current prospective trial is to investigate whether Luteal Stimulation (LS) results in equivalent euploid embryos with Follicular Stimulation (FS) in young reproductive age women. The use of the "oocyte donor model" allows extrapolation of the results and application of LS routinely not only in healthy women undergoing fertility preservation but also in all patients irrespective of the menstrual date. This may indeed allow widespread introduction of LS in IVF programs which may result in proper scheduling of ovarian stimulation which is a major issue in everyday clinical practice.

Given that the pharmacokinetics and follicular dynamics of 150μg corifollitropin alfa for luteal stimulation has never been evaluated, the current study of luteal stimulation with corifollitropin alfa could be very interesting for several reasons:

• Potentially immediate synchronization of oocyte donors with recipients aiming to fresh oocyte donation.
• Fertility preservation patients for medical, oncological and non-medical indication
• Any situation in which endometrial receptivity is not pursued.

Inclusion criteria

• Healthy eligible oocyte donors
• Age 18-34 years
• AFC >12 and AMH>1.5 ng/ml
• BMI 19-28kg/m2
• Body weight >60kg
• Both ovaries present
• Willing to participate in the study
• Willing to use non-hormonal contraception or not needing contraception Recipients will be eligible only if their partners' sperm which will be used for ICSI will be normal. Couples will be excluded in case of moderate to severe oligoasthenospermia.

Exclusion criteria

• Endometriosis
• AFC>20
• PCOS
• Low ovarian reserve
• Endocrine abnormalities
• Hormonal contraception
• Contraindication of hormonal treatment
• History of Ovarian Hyperstimulation Syndrome or hyper-response (> 30 follicles .

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