Older Dads Make for Riskier Pregnancies-Another study found that the risk of schizophrenia increased for children born to older fathers.

July 7, 2008, 3:02 pm
Older Dads Make for Riskier Pregnancies
Posted by Jacob Goldstein
We’re used to hearing about all the risks that increase for babies of mothers who get pregnant in their late 30s or early 40s. But in the past few years evidence has started to emerge that the age of the father matters, too.

The newest piece of the puzzle comes to us from Europe, where researchers at a Parisian fertility clinic found that miscarriages were significantly more frequent for older fathers.

Among fathers over 45, 32.4% of pregnancies ended in miscarriage; when the father was under 30, 13.7% of pregnancies ended in miscarriage. When the researchers adjusted for other risk factors such as the age of the mother, they found that the odds of miscarriage were 75% higher for fathers over 45 than for fathers under 35.

The finding was based on data from more than 17,000 cycles of intrauterine insemination, a standard fertility treatment in which sperm from the father is injected into the uterus of the mother. The results were calculated to adjust for variables including the age of the mother, and the study was presented at a medical conference going on now in Barcelona.

In general, risks seemed to increase sharply after fathers turned 40, Yves Menezo, one of the authors, said today when we got him on the phone.

Traditionally, Menezo said, “Nothing was said about the age of the male. Now we feel males should father before the age of 40.” He added: “In the overall population, you will find people able to father after this age, but there is a dramatically increasing chance of miscarriage.”

The issue of paternal age last came to our attention in 2006, when a study in the Archives of General Psychiatry found the risk of autism spectrum disorder was higher for children of fathers over 40, compared with fathers under 30. (One potential confounder noted by the authors: Fathers with some of the social deficits associated with autism spectrum disorders might also be more likely to have children at a later age.)

Another study found that the risk of schizophrenia increased for children born to older fathers........