Why paracetamol in pregnancy is cause for caution, not alarm

While some studies have raised concern about paracetamol use during pregnancy, current advice is the popular pain relief does not need to be entirely ruled out.

A recent review of some research published in Nature Reviews Endocrinology sparked concern among expectant parents after it recommended paracetamol be taken with caution due to potential impacts on foetal development.

As with any medication taken during pregnancy, the study’s authors concluded it was all about timing, dose and balancing the potential benefits of taking paracetamol against possible risks of untreated pain or fever to the unborn.

A report published in Australian Prescriber, stated inadequately managed ongoing pain can result in depression and anxiety, which can have an adverse effect on a woman’s physical and psychological wellbeing and potentially affect her pregnancy.

So, how can you safely manage pain if you need to?

What pain relief medication is safe to take during pregnancy?

A review from the Royal College of Obstetricians and Gynaecologists (RCOG) in London recommends avoiding all drugs, if possible, during the first trimester – up to 12 weeks of pregnancy – but if needed, paracetamol has “an excellent safety profile” and is the preferred pain medication during pregnancy and breastfeeding.

The Women’s hospital in Melbourne advises paracetamol can be used to treat mild to moderate pain, such as headaches, toothaches and muscle pain or to reduce fever during pregnancy, but to avoid nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin, ibuprofen and diclofenac, especially after 30 weeks.

A fact sheet by The Women’s states most medications used while pregnant will cross the placenta and reach the baby.

Any decision to start, stop, continue or change medication before or during pregnancy should be made in consultation with your doctor to avoid harm to the unborn.

Can paracetamol in pregnancy cause autism?

Two leading Australian medical experts insist there is little cause for alarm, despite a 10-year study from the Johns Hopkins University, which found an increased risk of attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) in children where paracetamol was present.

The study drew criticism for numerous limitations, including that it only measured paracetamol use around the time of childbirth.

Obstetrician, gynaecologist and fertility specialist Dr Alex Polyakov says one of the study’s major problems is 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,” Dr Polyakov 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.”

University of Melbourne developmental neurobiologist Professor Norman Saunders says this study suggests an association – not causation.

“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,” Prof Saunders says.

“These limitations make it difficult to assess influence of other factors that might contribute to ASD and ADHD”.”

How can expectant mothers safely take pain relief?

The Nature Reviews Endocrinology report recommends paracetamol can safely be used by pregnant women at the lowest effective dose for the shortest possible time.

Dr Polyakov agrees.

“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.”

Written by Dilvin Yasa.

Updated March 2022.