• Erythromycin is an antibiotic given for urinary and chest infections
  • Is prescribed during recurrent illness or for people allergic to penicillin
  • Researchers called for a safety review but stressed increased risk is small 
  • Overall, study found antibiotics taken during pregnancy were safe

Pregnant women have been warned that a type of antibiotic could harm their unborn baby.

Researchers from Great Ormond Street Hospital and University College London have linked erythromycin pills with epilepsy and cerebral palsy.

The study tracked the health of babies born to 200,000 British women. Overall, the babies born to women who took antibiotics were no more likely to develop epilepsy or cerebral palsy. 

However out of every 150 women given a macrolide rather than penicillin, there was one more baby born with cerebral palsy or epilepsy.

Researcher Professor Ruth Gilbert advised pregnant women to keep taking any antibiotics that they are prescribed – as an infection is likely to harm their baby.



Erythromycin are from the macrolide family of antibiotics.

Macrolides are used to treat urinary and chest infections and are particularly likely to be given during recurrent illness or if a woman is allergic to penicillin.

And she stressed that any increased risk to the unborn child posed by the pills would be extremely small.

However, with four previous studies raising concerns about the pills, she said it was time for the pills to be thoroughly reviewed by the Medicines and Healthcare Products Regulatory Agency (MHRA).

Professor Andrew Whitelaw, of Bristol University, warned that a bad infection could end up killing both the mother and her child.

But he added: ‘Nevertheless, drug treatment in pregnancy requires a very high level of safety and it will not surprise me if the regulatory authorities advise doctors to avoid or severely restrict macrolides in pregnancy’.

Others said that the study does not prove that macrolides are harmful, as it could be that the bugs they are used treat are more likely to damage the brain than other infections.

Dr Christoph Lees, of Imperial College London, said: ‘One thing is for sure: pregnant women should definitely take antibiotics when prescribed them as the risk of untreated infection to the pregnancy can be catastrophic.

‘To put things in context, the extra risk to their baby of being prescribed macrolides, if indeed there is a risk, is very tiny.’

The medicines’ watchdog, the MHRA, said it has already sought independent advice on the study and it does not consider that the research provides proper proof that macrolides are dangerous.

A spokesman said: ‘Importantly, this study found no overall evidence of harm when antibiotics are prescribed in pregnancy.

‘Any pregnant woman who has been prescribed antibiotics should continue to take them as instructed and speak to their healthcare professional if they have any questions.’

Source: The Daily Mail