Is it safe to take paracetamol during pregnancy?

A new study links paracetamol use in pregnancy to an increased risk of autism and ADHD in children, but is there really any cause for concern?

As autism rates continue to rise (now about one in 70 according to Autism Spectrum Australia – an increase of approximately 40 per cent since 2014), so too do the number of studies looking into possible causes.

While theories focusing on maternal and paternal factors abound, a new international study published in JAMA Psychiatry suggests paracetamol use during pregnancy may be linked to an increased risk in both childhood attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD).

Considering many pregnant women will require some form of pain relief during pregnancy, it may be an unsettling thought – but should we really be worried?

What the study says

In the 10-year study of almost 1000 mother-infant pairs by Johns Hopkins University Bloomberg School of Public Health, researchers examined umbilical cord blood samples for traces of paracetamol and found an increased risk of ADHD and ASD in children where the drug was present.

The study only measured paracetamol use around the time of childbirth.

The researchers concluded their findings supported previous studies into the association between prenatal and perinatal acetaminophen (paracetamol) exposure and childhood neuro-developmental risk.

They added the study warranted additional investigations.

What the experts say about paracetamol use in pregnancy

While some Australian medical experts say the study is an improvement on previous research (because researchers could measure paracetamol and metabolites in placental cord, while previous studies have relied on self-reporting by patients), they insist there is little cause for alarm.

This study suggests an association – not causation, explains University of Melbourne developmental neurobiologist Professor Norman Saunders.

“It was not a prospective study as claimed by the authors, as the patient sample was taken from a long-established patient database; also, there was no pregnant patient group who had not taken paracetamol. These limitations make it difficult to assess influence of other factors that might contribute to ASD and ADHD,” he says.

Royal Women’s Hospital obstetrician, gynaecologist and fertility specialist Dr Alex Polyakov says one of the study’s major problems is that not all children were followed up with neurodevelopmental testing for a number of years.

“This significant selection bias is evident in extremely high prevalence of all neurodevelopmental conditions in this cohort, with only 32.8 per cent of children that were included in this study not receiving a diagnosis of either ADHD, ASD, DD or some combination of the three,” he says.

“The applicability of the study’s findings to general population, where the prevalence of neurodevelopmental conditions is generally accepted to be less than 5 per cent, is highly questionable.”

What should Australian mothers do?

Prof Saunders says according to the current Australian Medicines Handbook, paracetamol is considered safe to use in pregnancy and during breastfeeding.

“In the light of this and other published information it is high time for this advice to be modified,” he says.

Dr Polyakov, however, is quick to reassure mothers.

“Nothing in this study indicates an occasional intake of a couple of paracetamol tablets while pregnant would have any effect on the risk of ADHD/ASD,” he says.

“Like any medication however, paracetamol is not risk-free and should only be taken if necessary, especially in pregnancy.

“Based on this study’s findings, it may be best to avoid paracetamol around the time of labour and delivery.

“It may also be prudent to increase the time interval between doses to six to eight hours rather than the usually recommended four to six hours.”

If you have any concerns regarding paracetamol use during pregnancy and beyond, speak to your GP.

Key points about paracetamol in pregnancy:

  • This study suggests a link between paracetamol use in late pregnancy and increased risk of ADHD and autism. It does not suggest that paracetamol use is the cause.
  • Independent experts have pointed out flaws in the research, including a far higher rate of ADHD and autism in the study group than you would see in a general population.
  • Current official Australian advice is that paracetamol use is safe during pregnancy and breastfeeding.
  • Experts recommend taking any medication, including paracetamol, only if necessary.
  • Speak to your GP or pharmacist if you have any questions or concerns.

Written by Dilvin Yasa