IVF babies at risk of defects

By STEVE CONNOR

Babies born after in vitro fertilisation (IVF) are three times more likely to develop neurological disorders including cerebral palsy than children conceived naturally, a study has found.

Scientists believe the findings could be explained by the complications that often arise when two or more IVF embryos share the same womb, rather than because of the IVF techniques themselves.

Dr Bo Stromberg, who led the investigation at the University Children's Hospital in Uppsala, Sweden, said the findings supported the view that only one IVF embryo should be implanted into a woman rather than the two or more routinely used in many countries.

"We think that IVF is a good treatment and a vital option for couples who can't have babies naturally, but we have to think of a baby's future life, and not just that of the couple," Stromberg said.

The study, which used Sweden's extensive health records, compared 5680 IVF children aged between 18 months and 14 years with 11,360 youngsters of the same age who were conceived naturally.

Stromberg also compared twin births with single births. IVF in Sweden produces a relatively high number of twins because two embryos are routinely implanted into patients to raise the chances of a successful pregnancy.

The scientists say in their report, published in The Lancet: "Our findings show that children born after IVF have an increased risk of needing treatment in a childhood disability centre. Our results can largely be, though not solely, explained by the high frequency of twins born, and by low birthweight and low gestational age, but an effect on the IVF procedure per se or other factors not adjusted for cannot be excluded."

Twenty-three years have passed 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 of 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.

- INDEPENDENT

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