Tue Sep 28

Take care with paracetamol when pregnant — but don't let pain or fever go unchecked

Written by Luke Grzeskowiak, Channel 7 Children's Research Foundation Fellow in Medicines Use and Safety - Flinders University & South Australian Health & Medical Research Institute, Flinders University

Pregnancy comes with aches and pains and heightened anxiety about what we put into the body.

A new article published in Nature Reviews Endocrinology ^[1] has urged caution around taking paracetamol during pregnancy. The paper is a “consensus statement” that brings together analysis by a panel of experts who looked at evidence from human and animal studies of paracetamol use in pregnancy.

Paracetamol use during pregnancy may alter fetal development, say the authors, with long-lasting effects on child health. The authors call for improved education for health-care professionals and patients, less paracetamol use during pregnancy and further research.

Alert but not alarmed

At first glance, calls to minimise paracetamol use during pregnancy are alarming. For those who have taken paracetamol (commonly marketed in Australia as Panadol, Herron Paracetamol, Panamax, Chemist Own or Dymadon) during pregnancy, this could cause anxiety.

This new consensus statement calls for caution, but not concern. The proposed recommendations are largely consistent with current advice ^[2] provided to pregnant women in Australia.

With any medication in pregnancy, there needs to be a careful balance between treating a maternal condition and protecting the unborn. A trusted health care provider can help reach an informed decision. Paracetamol is no different.

Paracetamol is the active ingredient in hundreds of prescription and non-prescription medications. Shutterstock ^[3]

What are the concerns?

Worldwide, more than 50% of pregnant women ^[4] use paracetamol to treat pain and/or fever. Paracetamol is the active ingredient in hundreds of prescription and non-prescription products. It has been widely regarded for many years as safe to use during pregnancy.

Some, but not all, observational studies in humans suggest paracetamol use during pregnancy may alter fetal development ^[5]. The new statement notes that paracetamol has been linked to increased risk of certain neurodevelopmental, reproductive and urogenital disorders ^[6].

But these studies have limitations. Researchers have found it hard to distinguish the effects of paracetamol from the effects of underlying illness. And there are potential inaccuracies in recording the amount and timing of paracetamol use across an entire pregnancy as are highlighted in the accompanying editorial ^[7].

Possible risks of paracetamol use in pregnancy are supported by a number of animal studies, the authors say. For this reason, caution regarding paracetamol use has been advised until a definitive link can be proven or disproven.

It’s worth noting the available evidence suggests any possible harms of paracetamol are likely to be dose-related. As highlighted by the review article, most increased risks have been linked with use in pregnancy for more than two or four weeks ^[8]. Current evidence suggests limited risks to unborn babies when paracetamol is taken short term.

Timing is also important. Taking paracetamol during the first trimester has been linked to an increased risk of reproductive and urogenital disorders. Neurodevelopmental disorders have been linked to use in the second or third trimester.

When the benefits outweigh the risks

The potential benefits of taking medication need to be weighed against any possible risks. Paracetamol is recognised as an important medication for treating pain and fever during pregnancy.

If left untreated, these conditions could harm the fetus or the pregnant person (the Nature editorial ^[10] and statement ^[11] say the expert advice is “relevant for all people who wish to become pregnant, including transgender individuals, non-binary people and intersex people”).

The review authors recognise the potential benefits of paracetamol use ^[12] and note untreated pain has been linked to increased risks of depression or anxiety as well as hypertension during pregnancy. Fever in pregnancy is a risk factor for multiple neonatal and childhood disorders, including certain birth defects and miscarriage. There is evidence to suggest that use of paracetamol may reduce these risks.

What are the alternatives?

The optimal management of pain or fever during pregnancy has not been well studied and treatment options remain limited.

Non-steroidal anti-inflammatory medications (such as ibuprofen) have been linked to miscarriage ^[14] when used in the first trimester, whereas use after 30 weeks’ gestation can negatively impact kidney and heart/lung function ^[15] in the fetus. For this reason non-steroidal anti-inflammatory medications are best avoided ^[16] unless advised by a healthcare professional. The same goes for strong pain medications such as opioids, which should be reserved for the management of severe pain ^[17]. Paracetamol remains the best choice for the short-term treatment of pain and/or fever during pregnancy.

It is also important to identify the cause of the pain or fever, particularly during pregnancy. Discussions about paracetamol use can lead to further investigation, recommendations for non-medication treatments or the need for different medications.

Safe options for pain management during pregnancy are limited. Shutterstock ^[18]

The bottom line

The new consensus statement does not alter existing recommendations regarding paracetamol use during pregnancy. But it does highlight the importance of thinking carefully before using any medications during pregnancy and raises greater awareness about how challenging making informed decisions about medication use can be.

Better evidence is needed to support decision-making during pregnancy and reduce unnecessary anxiety and concern.

Paracetamol use during pregnancy should be discussed with a health-care professional and used at the lowest effective dose for the shortest possible duration. Non-medication therapies for treating pain or fever should be tried before or in addition to paracetamol. When indicated, short-term use of paracetamol remains the safest medication for the treatment of pain and/or fever during pregnancy.