A report claims there is an increased risk of autism in second babies when their birth falls shortly after a mother's first pregnancy.
Researchers at Columbia University in New York City studied 600,000 sibling pairs and found the risk of the second child developing autism was significantly higher if there were fewer than 36 months between the pregnancies.
The highest risk was associated with pregnancies less than a year apart.
Previous research has found that closely spaced births carry a higher risk of premature and low birth-weight babies.
Royal College of Obstetricians and Gynaecologists spokesman Dr Patrick O'Brien said women have long been advised to leave a 12 month gap between pregnancies, but added parents shouldn't be 'scared' by the report:
'People shouldn't get too scared because the absolute risk of autism in this study remains very low – even when the gap between pregnancies is less than a year.'
'However, for various reasons – and now it seems the risk of autism – it makes sense to delay getting pregnant with your second baby for at least a year.'
What do you think?
Have you had closely spaced pregnancies?