As more older men become fathers, researchers are focusing on potential health effects of their children. Initial studies show a link between older fathers and children with various genetic defects. But some caution that more research is needed before drawing such conclusive links.
Biologically speaking, men have the ability to reproduce until relatively late in life. Some, like Hollywood acting legend Robert De Niro, choose to exercise that option. De Niro, 68, just welcomed the arrival of his seventh child, a daughter. Last year, a man in northern India reportedly became the world’s oldest father at 94.
For many reasons – including the life expectancy of the dad – fathering children at an advanced age can be a difficult choice. But is it also unsafe for the child?
Several recent studies have found that the children of older fathers stand a greater chance of being born with serious health problems, or suffering from them at some time in their life. Genetic defects resulting in malformations, malign tumors, or Marfan Syndrome (a disorder of the connective tissue) are often seen in the children of older fathers and explain why, in most countries, sperm donors may not be older than 40.
Such studies are of particular concern to Swiss fertility expert Dr. Peter Fehr, who notes that in Switzerland the number of men becoming fathers at the age of 50 or above is steadily rising. “Increasingly, we’re seeing an older man with a younger second wife from Eastern Europe who absolutely wants kids,” he says.
Scientists are recognizing that more diseases than previously thought have a connection to the age of the father. For children fathered by men over 40, problems may already begin in the womb. A team of researchers at the New York Medical School observed that the older the father is, the more likely the mother-to-be — regardless of her age — was to suffer from high blood pressure during pregnancy. Women thus afflicted have to be carefully monitored because of the danger of kidney failure and hemorrhaging if the condition worsens. That, in turn, can result in asphyxiation of the child. The risk of miscarriage also increased.
Doctors at Aarhus University in Denmark have shown that the risk of early birth (before the 32nd week) was twice as high when the father was over 50 by comparison to fathers under 25. Older fathers can also negatively impact a child’s health later on: bioscientists at Sweden’s Karolinska Institute have shown that brain tumors and leukemia are more frequent in children of older fathers.
Mental illness can in some cases be traced to the age of the father as well: twice as many children fathered by men over 50 suffered from autism as did those fathered by men under 29, according to a recent report by doctors at the Mount Sinai School of Medicine in New York. Swedish researchers came to similar conclusions with regard to manic-depressive illnesses.
But Peter Propping, chairman of the German Society for Human Genetics, cautions that “a lot of this is speculation because all of these illnesses can’t be caused by point mutation.” It is often unclear what causes complicated conditions like autism or brain tumors. Doctors suspect combinations of multiple causes, and say it is unwise to leap to conclusions about the relation of the age of the father to an illness, since in some cases, results have still been based on a single study. No doubt, more research is on the way.
Read the full story in German by Moritz Pompl
