There appears to be a direct correlation between galactosemia and male infertility, according to researchers from the Department of Clinical Genetics out of Maastricht University Medical Center. Twenty-six men with galactosemia were compared to 46 controls (no galactosemia diagnosis). According to the study findings, men with the condition measured lower levels of testosterone, inhibin B and sperm concentration. Whereas, the same group measured higher than the control group for sex hormone binding globulin. Men in the galactosemia group also suffered from cryptorchidism more often than men in the control group.

Conclusion: Lower testosterone and inhibin B are not necessarily the cause of severe infertility, but could have a negative impact on reproductive function. The lower sperm count and increased risk of cryptorchidism (undescended or missing testicle) could also hamper reproductive attempts. Further research is needed to fully define the role of galactosemia in reproduction and fertility.

Source: Gubbels CS, Welt CK, Dumoulin JC, Robben SG, Gordon CM, Dunselman GA, Rubio-Gozalbo ME, Berry GT. The male reproductive system in classic galactosemia: cryptorchidism and low semen volume. J Inherit Metab Dis. 2012 Oct 11.

http://www.ncbi.nlm.nih.gov/pubmed/23053469