# Resolution of Fetal Arrhythmia Following Maternal Discontinuation of Doxylamine (Unisom): A Case Report and Review

## TL;DR

A pregnant woman's fetus had arrhythmias that resolved after she stopped taking Unisom, suggesting the medication may cause fetal heart rhythm issues.

## Contribution

This case report suggests doxylamine may have a proarrhythmic effect during pregnancy.

## Key findings

- Fetal arrhythmias resolved within a week after discontinuing doxylamine.
- Postnatal evaluation showed normal heart function with no arrhythmia recurrence.

## Abstract

We report a case of a 36-year-old pregnant woman whose fetus exhibited frequent premature ventricular contractions (PVCs) and occasional probable premature atrial contractions (PACs) at 23 weeks' gestation. The patient was taking Unisom for nausea. After discontinuing the medication, the fetal arrhythmias resolved within a week. Postnatal evaluation showed a normal ECG, a normal QT interval, and no recurrence of arrhythmias. This case highlights the importance of thoroughly reviewing maternal medications when assessing fetal arrhythmia and suggests a possible proarrhythmic effect of doxylamine during pregnancy.