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June 1, 2020

Contextualizing Potential Risks of Medications in Pregnancy for the Newborn—the Case of Ondansetron

Author Affiliations
  • 1Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
  • 2Department of Epidemiology, Harvard T. H. Chan School of Public Health, Boston, Massachusetts
  • 3Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
JAMA Pediatr. 2020;174(8):747-748. doi:10.1001/jamapediatrics.2020.1325

Medication use in pregnancy is common: 50% to 80% of pregnant women in the US use prescription medications. However, because pregnant women are generally excluded from clinical trials of new medications, little is known about their safety during pregnancy at the time of approval. During the postmarketing period, as pregnant women start using the medication, signals of potential safety risks may emerge. In some instances, the risks are clearly incompatible with use of the medication during pregnancy (eg, thalidomide). However, more commonly, signals of risk emerge that are relatively weak and for outcomes that are relatively rare, creating a challenging situation for patients, prescribers, and regulators. On one hand, there is a desire to avoid using any medication during pregnancy that might have an adverse effect on the developing fetus or the mother. On the other hand, there is often a need to treat medical issues that complicate pregnancy. Regulators, in particular, face a challenge when weak signals of risk emerge given their mandate to protect the public health and prevent the unsafe use of medication. They have to decide how to react to the new information, communicate the risk, and inform clinical practice in a way that mitigates the risk while safeguarding treatment access for women for whom the benefits outweigh the risks.

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1 Comment for this article
Primum Non Nocere
Abubakar Naida, MD | Millington Pediatrics, Millington, TN. Practicing Neonatologist and Pediatrician
I think it’s reasonable to ban the use of ondansetron during the first trimester of any pregnancy due to the relative risk of its association with adverse effects, albeit minuscule. What was not addressed at all is the life-long burden of cleft lip on the child even after surgical correction. Some kids might not like to have facial disfiguration for life from the resultant scarring. Additionally, the emotional burden to the parents, other family members including the grandparents, as well as the resultant hospitalization to correct the defect under GA and duration of stay in hospital are also important. Yes, the risk is low but the burden of even a single case is immense. Lastly, it’s quite burdensome to the sick moms to make a sound decision while they are sick. So, the drug should just be avoided in the first trimester for all moms!