COUPLES WHO STRUGGLE to conceive naturally and turn to in vitro fertilisation (IVF) in the hope of becoming parents may face double the risk of their child developing cerebral palsy, according to new scientific research.

Cerebral palsy – a neurological condition which can result in speech problems, muscular stiffness and curvature of the spine – has been linked to children born through IVF in the past. However the study by researchers at the University of Aarhus in Denmark has shown for the first time that this might be a direct result of the IVF treatment itself rather than a consequence of a couple’s fertility problems.

In the study, which was published today in the journal Human Reproduction, included more than 90,000 children. Researchers concluded that IVF doubled the risk of cerebral palsy, with about one in every 176 children born through IVF having the condition, compared to the British average of about one in 400.

The result remained the same regardless of whether the mother smoked, or whether the baby was premature or a twin.

Dr Jin Lieang Zhu, an epidemiologist, and his team found that there was no statistically significant difference in rates between those whose mothers took less than two months to conceive, and those who took more than a year. However, there was a difference between those who took over a year to conceive and those who became pregnant through IVF.

This difference was not statistically significant, the report says, but adds that this was probably due to the small number of cases of cerebral palsy in the test group. While Dr Zhu stressed that the overall risk of having a child with cerebral palsy was still low, he and his team nevertheless concluded that IVF “confers a risk of cerebral palsy”.

UK experts said despite the low risk the issue needed to be taken seriously.

Recently, a study in Sweden suggested that the recent trend nowadays of putting just one embryo – rather than two – into a woman as part of IVF was reducing the number of children born with cerebral palsy.

One of the authors of that study, Professor Karl Nygren, is quoted by the BBC as saying the extra risk “may have disappeared” in countries which transferred only a single embryo.

However, Professor Richard Fleming from the Glasgow Centre for Reproductive Medicine, said the problem still needed serious attention: “Single embryo transfer will improve matters,” he said “But [it will] not solve the problem entirely.”