Women who are overweight during pregnancy are more likely to have children with autism, a new study has found.
Researchers from Central South University in China carried out a meta-analysis, combining findings from independent studies to investigate the link between maternal obesity and autism.
They used worldwide data that involved 200,000 people.
Obese women with high blood sugar levels were nearly 47% more likely to have a child with autism compared to normal weight mothers.
Researchers said, according to the Daily Mail: "Our findings suggest that maternal obesity is associated with autism spectrum disorder.
"This meta-analysis reveals that maternal obesity might increase autism risk in children. Further studies are recommended to confirm the result."
The results were published in the latest issue of the Journal of Autism and Developmental Disorders.
Previous studies have alluded to this correlation before.
In 2012, researchers from University of California found that obese expectant mothers were 1.6 times more likely to have a son or daughter with autism, and were more than twice as likely to have a child with other developmental difficulties.
The researchers have stated one theory is overweight women have high blood sugar levels, which may have a detrimental impact on the development of the brain.
However, Dr Helen Webberley MBChB MRCGP MFSRH, dedicated GP for www.oxfordonlinepharmacy.co.uk, said a larger, more detailed study needs to be done to confirm any solid link.
She told HuffPost UK Parents: "This is an interesting analysis of lots of studies, and it certainly shows that more work is needed in this field.
"To be absolutely sure of a link we need to prospectively follow a large number of pregnant women and compare diagnoses of autism in relation to maternal weight.
"It is very easy to find incidental relationships when looking at studies that are not set out to look at that particular outcome. Autism is a very hard condition to understand and can be difficult to diagnose for certain, we need to do a lot more work in this field.
"Many children with behavioural problems arising from issues such as poor parenting can have symptoms which overlap with conditions on the autistic spectrum, and this may occur more frequently in families with lower socio-economic status and less healthy lifestyles."
Richard Mills, research director at Research Autism, told the Daily Mail: "It is an interesting study. More work is needed, and it is likely that a number of factors will be involved.
"We are also increasingly seeing evidence that there are several types of autism... which would suggest that there are likely to be different causes."