Paracetamol pregnancy warning

A study of thousands of women found the chance of a baby who suffered from wheezing was roughly doubled in women who took it every day late in pregnancy.

While having a wheezing child is no guarantee of that child becoming asthmatic, it is a risk factor for asthma.

However, experts say that paracetamol remains the safest painkiller for use during pregnancy.

The study was carried out by researchers at King's College London, who interviewed more than 9,000 pregnant mothers, asking them about their painkiller use.

Those who took paracetamol or aspirin most days or even daily were described as "frequent" users.

Small sample

Very few women - perhaps only 1% of the sample - took painkillers to this extent.

Taking paracetamol frequently in the latter half of pregnancy was linked to a doubling in the risk of wheeze.

The researchers suggested that, in high doses, one of the chemicals produced when paracetamol is broken down can be toxic to the liver and kidney.

Animal studies have also suggested that very high doses could damage the airways, although there is no direct evidence that this chemical could cause harm to the developing lungs of the foetus.

Caution

The authors of the paper said that there was no link between wheeze and more moderate use of paracetamol during pregnancy, and that it was still the safest of all the most popular types of painkiller.

However, they cautioned against more frequent use.

Dr John Harvey, from the British Thoracic Society, echoed this.

He said: "This is one of the first studies to show a link between paracetamol use in late pregnancy and wheezing in early childhood.

"Further research is needed in this area - particularly into dosage and frequency of paracetamol use - and should be fast-tracked.

"Paracetamol, however remains the safest analgesic for pregnant women and only a very small percentage of pregnant women in this study took paracetamol daily or on most days during late pregnancy.

"Nevertheless, we would recommend caution to pregnant women taking paracetamol and advise them to consult their GP if they are worried."

The research was published in the journal Thorax.