_{The basic of IVM is the maturing in vitro of oocytes from the G.V stage of development to the MII stage.}

An attractive alteration to ovarian stimulation in these women would therefore be to retrieve oocyte from unstimulated women and consequently mature and fertilize these oocytes in vitro avoiding hormonal stimulation and reducing the cost of hormonal injection.

 Women suffering from PCOS (Polycystic Ovarian syndrome) are extremely sensitive to stimulation with exogenous gonadotrophin in assisted reproduction, and they have an increased risk of developing OHSS (Ovarian Hyperstimulation syndrome).

 Severe OHSS is associated with occasional severe complications such as thromboembolism, adult respiratory distress (ARDS) and, rarely, death.  The long-term side effects of gonadotropin stimulation are unknown. The recovery of immature oocytes followed by in vitro maturation (IVM) of these oocytes could be developed as a new method for the treatment of women with infertility.  The benefits of IVM include avoiding the side effects of GnRHa and gonadotrophins, avoiding the required ultrasound and serum monitoring (therapy reducing direct and indirect costs), and avoiding the risks of ovarian stimulation – including OHSS).