Another study has emerged, where the results of their research point to the birth weight of your baby potentially being a marker for autism.
According to Professor Kathryn Abel -
There is a 60 per cent increased threat of the condition in infants who were 10lb or more at birth.
A similar increase in risk for babies with low birth-weight because their growth in the womb was poor was also recorded.
The study provides the strongest evidence so far that the danger of autism is greater in babies whose growth in the womb was either poor or excessive.
Researchers believe a poorly functioning placenta may lead to abnormalities of growth in the baby’s body and brain.
She said: ‘Foetal growth is influenced by genetic and non-genetic factors. We have shown for the first time categorically that abnormal foetal growth in both directions increases risk of autism spectrum disorder.’
Researchers looked at data from the Stockholm Youth Cohort. This is a Swedish database of health records of thousands of children aged up to 17 between 2001 and 2007.
Early ultrasound dating provides detailed weights as a baby grows during pregnancy. Infants and children are later given clinical assessments of their social, motor, language and cognitive abilities.
Altogether 40,000 health records were assessed. Researchers found 4,283 young people with autism and compared outcomes with 36,588 who did not have the condition.
The study found that bigger babies born weighing more than 9lb 14oz (4.5kg) showed a higher incidence of autism, as did smaller infants born weighing less than 5lb 7oz (2.5kg).
A baby who had poor foetal growth had a 63 per cent greater risk of developing autism compared to babies who grew normally. A baby who was large at birth had a 60 per cent greater risk.
This effect was independent of whether the baby was born prematurely, or after the expected date of delivery, says a report in The American Journal of Psychiatry.
Professor Abel said: ‘We think this increase in risk associated with extreme abnormal growth of the foetus shows that something is going wrong during development, possibly with the function of the placenta
‘Anything which encourages abnormalities of development and growth is likely to also affect development of the baby’s brain.
‘Risk appeared particularly high in those babies where they were growing poorly and continued in utero until after 40 weeks. This may be because they were exposed the longest to unhealthy conditions within the womb. We need more research into foetal growth, how it is controlled by the placenta and how this affects how the brain develops.’
My three boys were varied in birth weights - J was 8lbs 4ozs, O weighed 10lbs 8ozs, and W weighed in at 8lbs 7ozs. Although J is the one with the significant learning difficulties and autism, he does not fit in with this study. O with his birth weight is more of a candidate, but he is neuro typical, or 'normal' in Layman's terms.
What is apparent to me is the last paragraph 'exposed to the longest unhealthy conditions within the womb'. This pertains to me my theory of high levels of mercury in my system, due to my tuna fish obsession when pregnant with him. This was back when there were no restriction on the consumption of tuna fish in pregnancy. I had no warnings of the danger of mercury levels in tuna at that time. It was only when I became pregnant with O four years later that guidelines had been introduced. I avoided it during my pregnancy with O, and with W.
Again the time frame between O and W had made the tuna restriction even more definitive.
Mercury has been linked with brain function and learning difficulties.
The study performed by Professor Abel is another step forward. It is not a miracle finding, but there does seem to be an interesting link which I know will be studied deeper.
