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Closely Spaced Pregnancies Associated with Increased Autism Risk


Less than a week after the lead researcher of the debunked 1998 study tying autism to vaccination has been accused of fraud comes a study published online today in Pediatrics suggesting that a second baby conceived within a year of the birth of a first child may face a three-fold higher risk of autism. Second-borns conceived between 12 and 23 months after a first child’s birth had twice the risk of autism compared to babies conceived 3 or more years following an older sibling’s birth.

Researchers at Columbia University studied birth records from 662,730 second-born children from California, who were born between 1992 and 2002 and who didn’t have an older sibling with autism. According to data provided by California’s Department of Developmental Services, 3,137 second-borns in this group had received a diagnosis of autism by age 6. Because the birth records included information about parental education level, birth weight, and age, researchers were able to account for a number of factors in their calculations, but they still found a link between shorter intervals between births and a higher risk of autism.

Although researchers were not able to state definitively that delaying a second pregnancy would lower the risk of autism, the findings may indicate a change in the uterine environment in the years immediately following pregnancy, such as a deficiency in certain nutrients. Closely spaced pregnancies have also been linked to brain diseases like schizophrenia as well as a higher risk of prematurity.

Moms, would this latest study lead you to space your pregnancies further apart?