Successful pregnancies resulting from the use of prolonged-incubation human spermatozoa in gamete intrafallopian transfer.

Human spermatozoa that were incubated overnight at room temperature before intrafallopian transfer with freshly collected oocytes gave rise to successful pregnancies and normal live births. The resulting pregnancy rate per transfer of 50% (4 of 8) compared favorably with the average pregnancy rate of 41.8% (38 of 91), achieved by our standard spermatozoal preparation procedure that prepared the spermatozoa approximately 2 hours before the GIFT operation. This new approach for the preparation of human spermatozoa would be applicable to oligospermic patients and some GIFT patients whose partners may have difficulties in producing a semen specimen immediately before the GIFT operation.