The taking of antibiotics by expectant mothers while in premature labour may increase the chance of a child being born with cerebral palsy, according to research.
The seven-year study by the Medical Research Council (MRC) found babies had a greater risk of developing the disability if their mothers' waters had not broken and they were given antibiotics despite showing no signs of infection.
But the report found the risk was not greater where mothers had gone into premature labour and their waters had broken.
The current research followed up the Oracle trial completed seven years ago to see how children developed if their mothers had been given antibiotics during premature labour.
The MRC study, published in medical journal The Lancet, noted that parents reported a "small but statistically significant increase in the condition cerebral palsy" in their children if they had been given antibiotics during premature labour but their waters had not broken.
Sara Kenyon, of the University of Leicester who led the Oracle Children Study, said: "It is unclear why the follow-up showed this unexpected increase in the number of cases of cerebral palsy in babies born to the group of women whose waters had not broken and not in the other group."