Research, published in Paediatric and Perinatal Epidemiology, reports that childhood behaviour, memory, and IQ may be linked to paracetamol use during pregnancy.
Dr James Dear, Reader in Clinical Pharmacology, University of Edinburgh, said:
“This study suggests a link between behavioural problems in childhood and maternal use of paracetamol during pregnancy. A similar link has been suggested by other studies. The study is well designed and attempts to take into account confounding factors. However, this type of study can only demonstrate an association and cannot say that paracetamol use in pregnancy causes problems in childhood. Important questions remain such as what is the mechanism (if paracetamol is causative) and is there a safe dose (are the effects dose-related).
“At present, in my opinion, women should only use paracetamol in pregnancy if clearly needed and only continue to use it if paracetamol relives the symptom being treated. The lowest dose for the shortest time should be taken.”
Dr Pat O’Brien, Consultant Obstetrician and Spokesperson for the Royal College of Obstetricians and Gynaecologists, said:
“These results demonstrate only an association between paracetamol use and adverse outcomes. More research is needed to determine the causation.
“Previous studies have suggested associations between paracetamol use and adverse outcomes for the offspring, such as childhood asthma and behavioural problems. However, the US Food and Drug Administration (FDA) issued a safety announcement in 2015 that addressed these concerns and clarified that these studies had potential limitations in their design and included conflicting results.
“Current advice is that paracetamol remains safe for use in the treatment of mild to moderate pain in women during pregnancy and breastfeeding. If a woman has any concerns, or requires stronger pain relief, she should speak to her healthcare professional.”
An MHRA spokesperson said:
“The safety of all medicines is carefully monitored. We are aware of the study undertaken by Professor Golding and colleagues. The findings of this study are being carefully evaluated. Advice will be sought from our independent expert advisory group to determine whether the study findings have any implications for the safe use of these medicines in pregnancy.
“Our advice to patients and prescribers remains that if necessary, paracetamol can be used during pregnancy. Individuals should use the lowest possible dose that reduces pain and/or fever and use it for the shortest time possible. Patients are advised to contact their doctor or midwife if the pain and/or fever are not reduced or if the medicine is required with increasing frequency.”
Prof Andrew Whitelaw, Emeritus Professor of Neonatal Medicine, University of Bristol, said:
“This is a high quality large study in which the investigators have gone to great lengths to eliminate other reasons for attention deficit and hyperactivity. However, they were not able to collect detailed information on the reason for each pregnant woman taking paracetamol or the total dose.
“Paracetamol is often taken to relieve flu-like symptoms and also for mild inflammatory joint conditions or injuries. Since there is considerable evidence that maternal infections and inflammation can adversely effect the fetal brain, there is a possibility that, in some women, it is the reason for paracetamol, rather than the medication itself, which has affected the infant´s brain.
“Caution with any medication in pregnancy is wise but one has to consider what alternatives exist. Other drugs for pain are likely to cause more problems and, if pain is untreated, maternal stress has also been identified as a risk factor for the fetus.”
Dr Sarah Stock, Senior Clinical Lecturer, and Honorary Consultant in Maternal and Fetal Medicine, University of Edinburgh, said:
“The take home message for me is that paracetamol, taken in the middle part of pregnancy, was not associated with some of the outcome measures looked at such as memory and IQ, and that although there was an association with some measures of child behaviour this did not last past the time they leave primary school.
“Although paracetamol in pregnancy might be associated with some measures of parents’ perception of early childhood behaviour, the implications of these effects are not clear, and the evidence is by no means conclusive. Even though the analysis is carefully performed, we can’t be sure that other factors, such as the reason for taking paracetamol in the first place, aren’t contributing to the results.
“As the authors rightly conclude, further research is needed.
“Pregnant women have few options for pain relief or treatment of fever, and this study should not alter current recommendations for the sensible use of paracetamol if required.”
Prof Andrew Shennan, Professor of Obstetrics, King’s College London, said:
“Paracetamol is commonly taken in pregnancy and is thought to be safe, indeed is recommended for reducing high temperatures and for mild to moderate pain. As this study states, it could be the reason for taking the paracetamol – rather than the paracetamol itself – that is related to hyperactivity and attention issues in children. Preterm birth, for example, may result in more paracetamol use as women in early labour may use it to treat temperatures and pain related to early labour. The authors have not controlled for this, nor for many other pregnancy factors that can influence brain function, such as fetal growth. More research is needed.
“It remains reasonable to use paracetamol in pregnancy. Women should seek advice from their doctor if in doubt, as alternatives can cause unwanted effects in babies.”
Dr Rod Mitchell, Consultant Paediatric Endocrinologist, and Research Group Leader, MRC Centre for Reproductive Health, University of Edinburgh, said:
“This well conducted study in a large population of parents and children adds to a growing body of evidence that point to associations between paracetamol exposure in the womb and some aspects of childhood behaviour.
“A previous study has used the same cohort and provided similar results. However, the present study was able to use a different method to rule out additional factors that could be alternative reasons for the association. Importantly, the study required mothers to record paracetamol use at the time of pregnancy, which avoids bias related to recalling exposure many years later.
“Determining whether reported associations are causative and if so whether they are dependent on paracetamol dose or duration are important aspects that are not investigated in this study.
“Regarding the use of paracetamol in pregnancy, current NHS guidance provides a pragmatic approach. This involves limiting its use where possible and, if deemed necessary, to use paracetamol at the lowest effective dose for the shortest possible time.
“Whilst the study is robust and shows an association between in-utero paracetamol exposure and subsequent behavioural difficulties, it does not provide a causal link between exposure and outcome.”
‘Associations between paracetamol (acetaminophen) intake between 18 and 32 weeks gestation and neurocognitive outcomes in the child: a longitudinal cohort study’ by Jean Golding et al. was published in Paediatric and Perinatal Epidemiology at 00:01 UK time on Monday 16 September 2019.
Declared interests
Prof Andrew Whitelaw: “I have no conflict of interest.”
Dr Sarah Stock: “No conflicts of interest.”
Prof Andrew Shennan: “I have no conflicts.”
Dr Rod Mitchell: “Dr Mitchell leads a research group that investigates the effects of in-utero paracetamol exposure on reproductive development and fertility.”
None others received.