Conceiving Again Trebles Autism Risk

Women who conceive within a year after giving birth could be putting their next child at increased risk of autism.

Such babies are three times more likely to have the developmental disorder, says a study.

Researchers say that a woman's body needs time to recover from a pregnancy and that a baby conceived too quickly after childbirth may be deprived of vital nutrients, the journal Pediatrics reports.

The findings, based on a study of more than 600,000 California families, add to the growing evidence that closely spaced pregnancies can be harmful, according to the Daily Mail .

Previous studies have shown that women with two closely spaced pregnancies are at risk of delivering babies who are premature and of low birth weight.

The research looked at the incidence of autism among 663,000 second-born children in California born between 1992 and 2002.

Study author Keely Cheslack-Postava of Columbia University, New York, said: "These results suggest that children born after shorter intervals between pregnancies are at increased risk of developing autism.

The highest risk was associated with pregnancies spaced less than one year."

Second-child conceived within a year of an elder sibling's birth were 3.4 times more likely to have autism than a typical child of the same age.

Babies conceived 12 to 23 months after the first child's birth were 1.9 times more likely to have autism, while the risk was lowered to 1.2 times after a gap of two to three years between pregnancies.