Men with a rare disorder in which they carry extra female genes can still have children if they undergo a surgical procedure for collecting their sperm, according to a new study.
Men with Klinefelter's syndrome carry an extra copy of the X chromosome; normally men have one each of the X and Y chromosomes, and women have two X chromosomes. Men with Klinefelter's syndrome carry XXY, and the main effect of the disorder is less fertility.
However, Dr. Ranjith Ramasamy and colleagues at New York-Presbyterian Hospital in New York used a surgery technique to retrieve sperm from 45, or two-thirds, of their 68 patients. Of 91 total attempts, 62 were successful.
More than half - 57 percent - of the men's partners became pregnant after the sperm was combined with their partners' eggs in the laboratory, in a procedure known as in vitro fertilization. Not all of those pregnancies made it to term, however: Overall, 45 percent of those couples who attempted to conceive using in vitro fertilization had children.
The researchers report their results In the September Journal of Urology. Sperm retrieval was more likely to be successful in younger men, with success rates of 71 percent for men 22 to 30 years old, 86 percent for those 31 to 35, and 50 percent for those 36 to 52 years old, they report. The oldest patient to undergo successful retrieval was 45.
Sperm retrieval rates were lower among men given testosterone replacement therapy, which is not uncommon in men with Klinefelter's syndrome.
Given that sperm can be retrieved from men with the syndrome up until at least age 35, the researchers conclude, men should not rush to have their sperm obtained during adolescence, the authors conclude.
SOURCE: Journal of Urology, September 2009.