A Swedish study has identified for the first time a link between
chlamydia infection and male infertility. The study of 244
couples, reported in Human Reproduction (May 2004), found
decreased pregnancy rates in couples where men had IgG
antibodies. These antibodies act as a marker of previous or
persistent chlamydia infection. The results showed that, if a
man was IgG-positive, the couple's chance of achieving pregnancy
was lowered by 33%. The researchers recommended that testing for
IgG in both men and women should be part of routine infertility
examinations.