IVF babies 'at higher risk of cerebral palsy'

Children conceived using fertility treatment are three times as likely to develop neurological disorders such as cerebral palsy than children conceived naturally, a study reveals today, .

The findings follow research by doctors in Sweden who compared the incidence rate of neurological problems in 5,680 children born after in vitro fertilisation (IVF) treatment, and 11,360 children conceived naturally.

They discovered that IVF children were about three times as likely to have cerebral palsy, which is the name given to a group of conditions characterised by varying degrees of paralysis during infancy or early childhood. Symptoms include the muscle rigidity and involuntary movements.

It was also found that suspected slow developmentwas four times more common in children whose conception was assisted. However, twins born after IVF were no more at risk than twins in the general population, indicating a link with multiple pregnancies.

Dr Bo Stromberg, from Uppsala University Children's Hospital, said: ""These risks are largely due to the high frequency of twin pregnancies, low birthweight, and prematurity among babies born after IVF. To limit these risks we recommend that only one embryo should be transferred during IVF."

The study, published in the Lancet medical journal today, is the first large-scale investigation of its kind. It is 23 years since the first test-tube baby was born. Worldwide there are about 50,000 IVF children born a year, yet next to nothing is known about any possible long-term effects on their health.

The Swedish study was not big enough to discern any inherent problems with the IVF techniques used, such as the direct injection of a single sperm into an unfertilised egg, or the effects of inducing the production of eggs in a woman.

The Human Fertilisation and Embryology Authority (HFEA), which advises on IVF said it would consider the details of the study closely.

A spokesman said: "The HFEA has recently revised its guidelines on the number of embryos that should be transferred

in any IVF cycle from three to two in order to reduce further the incidence of multiple births, particularly higher order multiples, and the problems associated with them."

However, the Lancet carried an accompanying article by David Healy and Kerryn Saunders, from Monash University in Melbourne, Australia. They claimed the Swedish findings were inconclusive and called for further research.