[Intra-tubal embryo transfer. A new therapy in andrologic sterility]

The intratubal transfer of pronucleus or early cleavage stage embryos (2-8-cell stage) is a new method in the treatment of human infertility. Following transvaginal sonographic oocyte retrieval, in vitro fertilization is performed and the fertilized oocyte pronucleus-stage or embryos are transferred into the tube by laparoscopy. By comparison to GIFT (intratubal gamete transfer), fertilization under in vitro conditions offers the advantage that the success of the fertilization process can be examined. Therefore, this method can give important diagnostic information--especially in cases of poor sperm quality or unexplained infertility. After fertilization in vitro and transfer into the tube the embryonic development occurs in the physiological milieu of the oviduct. Up until the present, the new procedure was performed in 40 patients with male factor or unexplained infertility. In 11 cases (28%) a pregnancy could be achieved. One abortion, but no ectopic pregnancy was observed. No difference in the pregnancy rates could be observed between the transfer of pronucleus stage and the early cleavage stage embryos. This method combines the advantages of IVF and GIFT and offers a successful procedure for the treatment of infertility.