Children of women who took paracetamol during pregnancy had an increased risk of hyperactivity and attention problems compared with those whose mothers had not taken the medicine during pregnancy, even after accounting for social and other possible confounding factors, according to a new study* – although the difference had disappeared by the time the children reached the end of primary school. The authors said today in Paediatric and Perinatal Epidemiology that as previous studies have already linked paracetamol in pregnancy with possible problems in children including asthma and behavioural problems, women should be advised to be cautious when taking medication during pregnancy and to seek medical advice where necessary.
The research team pointed out that paracetamol is commonly used to relieve pain during pregnancy and is recommended as the treatment of choice by the NHS.
They analysed questionnaire data from Bristol’s Children of the 90s study, covering 14,062 children, to examine whether there were any effects of taking paracetamol in mid-pregnancy (18-32 weeks’ gestation) and the behaviour of the offspring between the ages of 6 month and 11 years, with memory and IQ tested up until the age of 17. They considered the results of the children’s memory, IQ and pre-school development tests, temperament and behaviour measures.
At seven months pregnant, 43% of the children’s mothers had reported taking paracetamol ‘sometimes’ or more often during the previous three months. The researchers used multiple regression to assess the level of association between paracetamol intake and each of 56 outcomes, after adjustment for 15 potential confounders, including the reasons for which the medication was taken, or social factors.
They reported that after adjustment, 12 of the 56 outcomes remained significantly associated. These were almost entirely features of hyperactive or attentive behaviour – being less adaptable at six months, having poorer persistence at 24 months, having elevated scores on the hyperactive behaviour scales at 42 and 47 months (maternal reports) and teacher reports of poor attention in school year 3 (age 7‑8 years). However, they said that by the time the children reached the end of primary school, 10-11 years old, there were no longer any associations. They added: “Boys appeared to be more susceptible than girls to possible behavioural effects of the drug.”
The study authors commented: “Our findings add to a series of results concerning evidence of the possible adverse effects of taking paracetamol during pregnancy such as issues with asthma or behaviour in the offspring. It reinforces the advice that women should be cautious when taking medication during pregnancy and to seek medical advice where necessary.
“It is important that our findings are tested in other studies – we were not in a position to show a causal link, rather an association between two outcomes. It would also be useful now to assess whether older children and adults are free of difficult behavioural problems if their mother had taken paracetamol.”
* Golding J, Gregory S, Clark R, et al. Associations between paracetamol (acetaminophen) intake between 18 and 32 weeks gestation and neurocognitive outcomes in the child: A longitudinal cohort study. Paediatr Perinat Epidemiol. 2019; 00: 1-10.