Human Reproduction vol.6 no.5 pp.727-729. 1991 Ureaplasma in semen and IVF J.M.Montagut1, S.Lepretre, J.Degoy2 and

'To whom correspondence should be addressed Ureaplasma urealyticum (U.U.) screening has been system-atically performed in tests carried out before IVF cycles. In 42 % of the cases (306 couples), at least one partner presented a monomicrobian U.U. infection. U.U. infection of at least one fraction of the split ejaculate was observed in 32 % of the cases and found in similar proportions at the prostatic and seminal vesicle levels. The U.U.-infected group presented a similar number of cytological abnormalities to the non-infected samples. However, there was a significant reduction in the pregnancy rate after embryo transfer in the infected group whereas U.U. did not alter fertilization parameters, embryo retrieval or pregnancy rates per puncture. The preliminary results of a complementary prospective study (70 couples) point to the likely role of sexually transmitte