So called May/December marriages in which there's a big age gap between the partners are not that unusual in Florida - especially where the “May” (younger partner) is female and the older, “December” partner is male. There is often a tacit “atta boy” attitude when such relationships produce children- even when the father is well into his 80’s.
However, while past research has looked at the negative effects of advanced maternal age at childbearing, more and more research suggests that beyond the fact that older fathers are not as energetic as younger dads, there are additional serious downsides to advanced paternal age at childbearing.
A 2010 study found that older paternal age strongly increased the risk of schizophrenia in sisters of affected females.
Published online in JAMA Psychiatry last month, a new collaborative study between researchers from Indiana University and Karolinska Institute in Stockholm looked at 2.6 million boys and girls born in Sweden between 1973 until 2001 and found that older fathers put their children at risk for higher rates for a number of psychiatric conditions as well as academic problems.
Specifically, a child born to a 45 year old father was 3.5 times more likely to be autistic, 13 times more likely to have attention deficit hyperactivity disorder, 25 times as likely to be bipolar, and 2.5 times more likely to have a psychotic disorder, be suicidal or have a substance abuse problem as compared to a child whose father was 24 when he or she was born.
Academic problems included low IQ scores, poor educational achievement and failing grades.
The older the father, the more likely that these problems would arise.
High levels of education and income were not found to overcome the negative effects of being an older father.
Unlike women who are born with all their eggs, men continue to produce sperm throughout their lives. However each time sperm replicates, there is an opportunity for a DNA mutation. Older men have been found to have a decreased percentage of normal sperm.
The principal investigator, Brian M. D'Onofrio, PhD speculates that with aging, men are increasingly exposed to various environmental toxins shown to cause mutations in sperm DNA.
A 2012 study published in the journal Nature adds credence to this theory (see video). The researchers looked at the genomes of dozens of families in Iceland and found that the older a father was at the time his child was born, the greater the mutations that child inherited and these mutations increased the risk of autism and schizophrenia.
Bottom line: while this latest study doesn’t resolve the issue as to when men may be too old to father a child, it should make one pause and consider the up versus downsides of being an “older” parent - especially for men over 45.