(RxWiki News) Much is made about a woman's biological clock, and the physical risks of pregnancy and childbirth that increase with age. But men may also have reason to re-think having children too late in life.
"Consider all the risks when having children later in life."
As men grow older, the genetic mutations in their sperm cells that can be passed on to children increase significantly. At puberty, a male's germ cells divide every 16 days. By the time he is 40, they will have gone through more than 600 cell divisions, giving much higher vulnerability to mutations.
A Dutch study analyzed 14,231 patients to measure the association between paternal age and autism, depression, schizophrenia and bipolar disorder. Scientists at the Rudolf Magnus Institute of Neuroscience found a significant increase in autism with paternal age, with fathers over 40 years old 3.3 times more likely to have an autistic child.
For men over 35, there was an association of higher schizophrenia. Increased risk for major depressive disorders was found in both older dads (over 40) and very young dads (under 20). No association was found for bipolar disorder.
Christina Hultman, an epidemiologist at the Karolinska Institute in Stockholm, found a similar correlation between older dads and autism. Studying 660 families, the offspring of men over 50 years old were 2.2 times more likely to have autism than children of fathers under 29 years old. "These findings provide the strongest evidence to date that advanced paternal age is a risk factor for autism in the offspring," Hultman wrote in her findings, published in Molecular Psychiatry.
The links don't seem to be limited to Western countries, either. Researchers in Malaysia found that delayed parenting, as well as extremely young parenting, impose mental health risks to children. The Malaysian study also found associations among children whose fathers were at least 11 years older than their mothers; for these children, their risk of mental health disorders was 24 percent, and it jumped to 42 percent if those fathers were 50 years or older.