Pretreatment of sperm with human follicular fluid for borderline male infertility.

To test the usefulness of human follicular fluid (FF) in treating male infertility, we incubated washed sperm specimens from 31 couples undergoing intrauterine insemination (IUI), for male and/or unexplained infertility, with either FF or Ham's F-10 medium (Gibco, Grand Island, NY), in alternating cycles in a randomized manner. Semen specimens from 28 men were incubated with either medium or FF. Incubations with FF have increased sperm penetration assay (SPA) scores from 24.8 +/- 17.3 to 34.3 +/- 13.6 (P less than 0.01). Incubation with heat-inactivized FF also has increased SPA scores, although to a lesser extent than noninactivized FF. Seventeen pregnancies occurred in the 31 couples treated by IUI (54.8%), 16 of them in FF-treated cycles (51.6%) and one in "control" IUI cycles (3.2%, P less than 0.01). All pregnancies occurred within four treatment cycles. Thus, IUI after sperm wash and preincubation with FF may be suggested for four to six cycles to couples with male factor and/or unexplained infertility who are reluctant to resort to artificial insemination by donor or adoption, before attempting the more costly and complex in vitro fertilization-embryo transfer procedure.