Couples applying for IVF are to be warned for the first time that their children face a greater risk of being born with birth defects, after new research.
The government's fertility watchdog has rewritten its guidelines to alert would-be parents to the health risks of artificial fertilisation methods.
The Human Fertilisation and Embryology Authority's new advice makes clear that test-tube babies are up to 30 per cent more likely to suffer from certain birth defects.
Doctors will be ordered to inform parents about the potential dangers of the treatment, which accounts for 10,000 births in Britain every year.
The move follows a major US study that showed that babies born using assisted reproductive techniques like IVF are twice as likely to suffer from some heart problems and cleft lip.
Test-tube babies are also at four times the risk of certain gastrointestinal conditions, according to analysis of data from the National Births Defects Prevention Study by researchers from the Centers for Disease Control and Prevention.
Other studies have not identified any link between IVF and birth defects, and the HFEA will continue to stress that most babies are born healthy.
But its experts have decided to alter guidelines that previously warned of the health risks associated with just one type of treatment known as ISCI - under which a single sperm is injected directly into the egg - to take into account growing fears about the safety of all forms of IVF.
"Following the publication of a US study into birth defects, HFEA's Scientific and Clinical Advances Committee reviewed our guidance and advice about the risks of treatment," an HFEA spokesman said.
"As with any medical procedure, it is important that patients understand what the treatment involves and what the risks may be. Our Code of Practice says that clinicians must tell patients about the possible side effects and risks of treatment, including any risks for the child."
Richard Kennedy of the British Fertility Society, which promotes fertility treatments, welcomed the move but said that only around 3.5 per cent of IVF babies have a birth defect, compared to 2.5 per cent of the general population.
"What we need to remember is that the overall risks of an abnormality occurring is increased with IVF but it is still a small risk. Nevertheless, patients need to be aware," he said.
