Fetal supraventricular tachycardia and maternal COVID-19 vaccination: is there any relationship?

Fetal supraventricular tachycardia accounts for 60-80% of the fetal tachyarrhythmias with prevalence ranging from 1/1000 to 1/25 000 pregnancies. It may be secondary to fetal anomalies or maternal factors. By reviewing the literature, there is no previous article that reports fetal arrhythmia after maternal vaccination. We present herein two cases of fetal supraventricular tachycardia following the administration of the Pfizer-BioNTech COVID-19 vaccine during pregnancy. Continued safety monitoring and more longitudinal follow-up are needed to evaluate the fetal impact after maternal COVID-19 vaccination.