OBJECTIVE To investigate if peritoneal oocyte and sperm transfer (POST) performed transvaginally is an effective treatment for nontubal infertility. METHODS Prospective study of 18 patients (4 with unexplained infertility, 13 with failed donor insemination, and 1 with male factor infertility) having 20 cycles of transvaginal POST in a specialist infertility unit. METHODS Ovarian stimulation was achieved with human menopausal gonadotropin (hMG) alone, hMG and clomiphene citrate, or gonadotropin-releasing hormone agonist with hMG. Oocyte recovery was performed transvaginally under ultrasound guidance, the pouch of Douglas rinsed repeatedly and an embryo transfer catheter used to transfer 4 x 10(6) progressively motile sperm in 1 mL and up to four oocytes into the pouch of Douglas. Luteal support was provided with human chorionic gonadotropin injections given 2 and 5 days later. RESULTS The mean age of the patients was 32.65 +/- 5.0, and the mean length of infertility 5.07 +/- 2.32 years. The mean number of oocytes transferred was 3.53 +/- 0.87. Three pregnancies were achieved in the failed donor insemination group and 1 each in those with unexplained and male factor infertility, giving overall clinical pregnancy and live birth rates of 25% and 20% per initiated cycle. All pregnancies were achieved in those who had three or four oocytes transferred. CONCLUSIONS Transvaginal POST is a useful assisted conception technique for the treatment of nontubal infertility.