Fathers Age Responsible for up to 50% of risk of Down Syndrome if the Mother is also over 40

July 1, 2003 -- Older fathers may contribute just as much as older mothers to the dramatic increase in Down syndrome risk faced by babies born to older couples. A new study found that older fathers were responsible for up to 50% of the rise in Down syndrome risk when the mother was also over 40.

Researchers say the number of births to parents over age 35 has more than doubled in the last 20 years and this has raised questions about the role of paternal age in the risk of genetic abnormalities and birth defects.


The study showed that the percentage of births to women over 35 grew from 8% of all births in 1983 to 17% in 1997, and the greatest change during this period was the number of births to mothers and fathers over 40 years old, which rose by 178% and 73%, respectively.


Researchers found that the rate of Down syndrome among parents over 40 was 60 per 10,000 births, which is six times higher than the rate found among couples under 35 years old. Older fathers over 40 had twice the rate of Down syndrome births compared with men 24 years old and younger when they had children with women over 35.


"Paternal age has an effect on Down syndrome but only in mothers 35 years old and older," write researcher Harry Fisch, MD, of the department of urology at Columbia-Presbyterian Medical Center in New York City, and colleagues. "In younger women, in whom age was not a risk factor for Down syndrome, there was no paternal effect."


Among older mothers over 40, researchers found that an increase of 50% in Down syndrome risk was attributable to the advanced age of the father.






"Young couples preparing for family planning must be aware that advanced parental age may not only result in increasing difficulties with fertility for the parents but that children born to older parents may be at higher risk for genetic abnormalities,"

Ageless Fatherhood? Maybe Not--- a very good article

KATHLEEN DOHENY
c. 2007 HealthDay News
Distributed by The New York Times Syndicate
This is the first of four recent article or TV spots on this vitally important topic.
Here are some extensive excerpts:


.............."Several studies have found that older fathers risk having children with medical problems, including Down syndrome. Fisch and his colleagues evaluated more than 3,400 cases of Down syndrome, finding that if the woman and the man were both over age 35 at the time of conception, the father's age played a role in prevalence of the disorder. This effect was most pronounced when the woman was over 40, the researchers found. And, in those cases, the incidence of Down syndrome was about 50 percent attributable to the sperm, the researchers said. The study was published in 2003 in The Journal of Urology.

In another study, Dr. Avraham Reichenberg, of Mount Sinai School of Medicine in New York City, found that advanced age for fathers is associated with an increased risk of autism. His team gathered data on the age of fathers of more than 318,000 people born in Israel during the 1980s. The researchers found that the chances of having a child with autism or a related disorder were about six times greater if the father was 40 or older, compared to men 29 or younger. The findings were published in the September 2006 issue of The Archives of General Psychiatry.

Still another study found that the risk of schizophrenia in children was tied to older age of the father. In the study, which included about 90,000 people, the researchers discovered that children whose fathers were 50 or older when they were born were nearly three times more likely to have the disorder than those born to younger fathers. That study was published in 2001 in The Archives of General Psychiatry.

Another study, published in 2002 in Human Reproduction, found a higher risk of miscarriage in mothers 35 and older and fathers 40 and older.

And, in 2004, The Journal of the American Medical Association reported that 20 different disorders in children, ranging from schizophrenia to skeletal disorders, have been linked to the advanced age of the father......................

Orignally published February 27, 2007