Wed May 24, 1:37 PM ET
NEW YORK (Reuters Health) - A man's fertility appears to decline
after the age of 40, in much the same way that a woman's ability to
conceive fades after 35, according to French researchers.
Their study, of nearly 2,000 couples undergoing fertility
treatment, found that pregnancy attempts were 70 percent more
likely to fail when the man was age 40 or older than if he were
younger than 30 -- regardless of his wife's age.
Because all the women in the study were completely sterile and
undergoing in vitro fertilization (IVF), the age of the fathers was
key. And while past studies have suggested that older men are less
likely to father children, the extent to which this was related to
biological changes or to decreased sexual activity has been
unclear.
"Our results provide, for the first time, strong evidence for a
paternal age effect on failure to conceive that is linked only to
biological male aging," the study authors report in the journal
Fertility and Sterility.
Dr. Elise de La Rochebrochard of the French national health
institute INSERM led the study.
According to the researchers, the lower IVF success rate among
relatively older men may be due to poorer-quality sperm.
It has long been known that women are less likely to conceive after
the age of 35 than before, de La Rochebrochard and her colleagues
note. But the current findings, they write, suggest that for men,
the age of 40 is similarly important.
"In reproduction," the researchers conclude, "age must no longer be
considered as the concern of the woman, but as that of the
couple."
SOURCE: Fertility and Sterility, May 2006.
Taken from:
http://news.yahoo.com/s/nm/20060524/hl_nm/biological_clock_dc
