Combination of IVF and IVM in naturally cycling women

For some time, there has been an increasing interest in mild approaches for fertility treatment, in particular IVF. In-vitro maturation (IVM) of immature eggs outside the ovaries followed by IVF is one of the potential treatments which eliminates the risk of ovarian hyperstimulation syndrome and minimizes the side-effects of medication. At the same time, natural-cycle IVF without hormonal stimulation is also experiencing a revival. By combining IVM and natural-cycle IVF, we aimed for to improve success rates in terms of more fertilized eggs to transfer and higher number of pregnancies and live births compared with sole natural-cycle IVF. At the same time, this project was a pilot study of eggs retrieved at this particular stage of the spontaneous menstrual cycle. Their reproductive capacity might be different from eggs retrieved in an earlier phase regarding maturation and fertilization capacity. The results showed that outcome was not better in the protocol combining IVM and natural-cycle IVF compared with natural-cycle IVF only. The reproductive capacity of the retrieved immature eggs seems less than reported in other IVM protocols. Though the combined concept of IVM and natural-cycle IVF is possible and there are ongoing pregnancies from both IVM and in-vivo matured eggs, we recommend either optimizing an IVM programme or using natural-cycle IVF rather than our original approach.