[Single-embryo transfer: Rennes' Hospital experience]

In 2005-2006, 905 punctures of oocytes were realised in the Assisted Reproductive Technology Centre of Rennes' Hospital in France, the source of 173 pregnancies after fresh embryos transfers and 185 pregnancies after frozen embryos transfers. The single-embryo transfer (SET) was proposed in all patients aged less than 38 years with at least two embryos type I or II on the first two cycles. Sixty-three percent of patients (n=293 cycles) chose the SET with 21.5% pregnancies through fresh embryo transfer. The SET with frozen embryos has been completed on 708 cycles with 16.8% of pregnancies per transfer. The cumulative rate of pregnancies by puncture is 39% and the overall risk of multiple pregnancies has dropped to 12%. The SET associated with an effective embryo cryopreservation therefore allows to reduce the risk of multiple births while maintaining a satisfactory pregnancy cumulative rate.