Outcome of gestational surrogacy according to IVF protocol.

Purpose: Surrogacy remains the only option for having a biologic child for a unique population of women with severe medical conditions. However, no study has looked at surrogacy outcome as a result of the type of ovarian stimulation of the intended mother [controlled ovarian stimulation (COH), modified natural cycle (MNC), and in vitro maturation (IVM)] for oocyte retrieval.

Methods: This is a retrospective study, including all intended mothers and gestational carriers in a tertiary, university affiliated, medical center, from 1998 to 2016.

Results: Fifty-two women underwent 252 oocyte retrieval cycles. The pregnancy outcome of 212 embryo transfer cycles (64 gestational carriers) was reviewed according to the origin of the embryo. The number of retrieved oocytes was significantly higher following COH (n = 132) compared with IVM (n = 58) and MNC cycles (n = 62) (p = 0.013 and p < 0.0001, respectively). Pregnancy rates for embryos transferred according to each protocol were similar. All pregnancies that ended in live births when oocytes from IVM cycles were used derived from transfers of retrieved mature and mixed mature and immature oocytes. Pregnancies that involved embryos derived solely from immature oocytes that further matured in vitro and were transferred to gestational carriers were unsuccessful.

Conclusions: MNC protocol is a good option to achieve pregnancy for intended mothers using gestational surrogacy who have contraindications to COH. The yield of IVM cycles in which immature oocytes are retrieved is inconclusive.