Advancing Maternal Age Is Associated
With Increasing Risk for Autism: A Review
and Meta-Analysis
The results of this meta-analysis support an association between advancing maternal age and risk of autism. The RR increased monotonically with increasing maternal age. The association persisted after the effects of paternal age and other potential confounders had been considered, supporting an independent relation between higher maternal age and autism. J. Am. Acad. Child Adolesc. Psychiatry, 2012;51(5):477–486.
This meta analysis looked at over 30,000 kids across all the studies. Here is the link if you want to read the whole paper
web.math.princeton.edu/~sswang/sandin_reichenberg12_maternal-age-ASD-metaanalysis.pdf
And here is an excerpt from why they did the study (sorry about the formatting, copying and pasting on an ipad is a complete nightmare)
M ost plausible neurodevelopmental theories of autism focus on genetic factors. However, there is evidence that non-heritable, pre-, or perinatal events, and/or environmental exposures are likely to also have a significant etiological role. Advanced maternal age is one of the most frequently studied risk factors for autism. However, the results from the individual studies are mixed, and the presence of the associations is still disputed.
It is important to examine the relationship between advanced maternal age and autism for two main reasons. First, an association between maternal age and autism may provide clues to the biological pathways leading to autism.
Older maternal age has been associated with increased rates of chromosomal abnormalities of autism focus on genetic factors.
still disputed.
It is important to examine the relationship of obstetric complications, possibly because of uterine muscle dysfunction and diminished blood supply with age. Cumulative Exposure to environmental toxins may also be im- portant for the association between advanced maternal age and neurological and psychiatric disorders
Second age of parenting has been increasing in the United States and Europe in recent de- cades, and an association between maternal age and autism may help to explain the increase in prevalence estimates of autism during the past two decades.
To elucidate the association between ad- vanced maternal age and autism, we conducted a systematic review and meta-analysis of all population-based epidemiological studies pub- lished until June 2011 that investigated the asso- ciation between advancing maternal age and autism
This article is discussed in an editorial by Dr. James C. Harris on page 461.
Supplemental material cited in this article is available online.
JOURNAL OF THE AMERICAN ACADEMY OF CHILD & ADOLESCENT PSYCHIATRY
VOLUME 51 NUMBER 5 MAY 2012 www.jaacap.org 477
SANDIN et al.