"ADOPTION AND IN SOME INSTANCES SPERM DONATION MAY BE ACCEPTABLE ALTERNATIVES TO OLDER FATHERS WANTING TO BUILD A HEALTHY FAMILY"

New Key to Autism


September 25, 2006

By Michael Craig Miller, M.D.
Harvard Medical School

Convincing Evidence
What Causes These Genetic Errors?
Should Older Men Stop Fathering Babies?
A study published in the September, 2006 issue of the Archives of General Psychiatry may give older prospective fathers pause before plunging into biological parenthood. The authors found a significant increase in the risk of autism and similar disorders as fathers got older.

What Is Autism?
Autism is a profoundly disabling disorder that starts in early childhood. The key features are:

Abnormal social development – little or no eye contact, prefers to be alone
Difficulty communicating – impaired language ability, uses gestures or pointing rather than words
Unusual behavior – spins objects, doesn't like being cuddled
Evidence of strong abilities sometimes in non-verbal areas, such as math or music
Older people with autism may have some ability to interact with people, but about two-thirds are mentally retarded and most cannot live on their own
Unfortunately, the incidence of this illness appears to be on the rise. Some experts think autism is diagnosed more often simply because more people are aware of it. But that's probably not the whole explanation.

Genetic factors almost certainly play a big role. So autism researchers are eager to discover anything that might increase a person's genetic vulnerability, such as delaying parenthood until age 40 or beyond.


The risk was smallest for children of fathers younger than 20 and greatest for children of fathers older than 50. A man in his 40s, for example, was almost 6 times as likely to have an autistic child as a man age 20. This relationship held even after researchers adjusted the results for the year of the person's birth, their socioeconomic status, or the mother’s age.

This is not the first discovery of its type. Healthcare professionals have long known that as parents age, the risk of giving birth to a child with certain illnesses goes up. Older mothers, for example, are more likely to have a child with Down syndrome. In recent years, studies have revealed a link between aging fathers and schizophrenia.

Convincing Evidence

The Archives study took advantage of the extraordinarily complete health records of over 300,000 Israeli men and women who underwent a complete health assessment when they were 17-year olds — draft age. This gave researchers a good way to determine the incidence of autism in the population. The researchers had access to intellectual, medical and psychiatric evaluations of almost all Israeli boys and three-quarters of girls. (Their identities were kept secret, however.) For most individuals, the father’s age at birth was known.

Although boys were more likely to develop autism than girls, the risk for girls also increased as fathers got older. When fathers were young, about 1 in 6 children with autism were girls. After fathers passed the 40 year-old mark, the proportion of girls with autism rose to about 1 in 3. This suggests that the genetic factors in play for offspring of older fathers are different from those for offspring of younger fathers...............



Until recently, health care professionals have focused almost exclusively on the mother's age as a risk factor for health problems in the child. But we now know that the father's age also adds to the risk of potentially devastating diseases. And there is no practical way to detect these illnesses during pregnancy. For those weighing the risks, the decision can be wrenching. Adoption and in some instances a sperm donation may be acceptable alternatives to older fathers wanting to build a healthy family.




Read the whole article by Dr. Michael Craig Miller here.



Michael Craig Miller, M.D. is Editor in Chief of the Harvard Mental Health Letter. He is also associate physician at Beth Israel Deaconess Medical Center and assistant professor at Harvard Medical School. He has been practicing psychiatry for more than 25 years and teaches in the Harvard Longwood Psychiatry Residency Program.