DOI: 10.1002/sono.70099 ISSN: 2202-8323
Testing the Fetal Heartbeat Myth: A Large Cohort Study Correlation With
NIPT
Sarah Dowthwaite, Karen Mizia ABSTRACT
Fetal sex determination before birth represents an important aspect of early parental pregnancy engagement. The fetal heartbeat myth claims female fetuses have faster heart rates compared with male fetuses. This large retrospective cohort study demonstrated clinically negligible differences in first‐trimester fetal heart rates (FHRs) between males and females at the time of noninvasive prenatal testing (NIPT). The mean female FHR measured 165 bpm and the mean male FHR measured 166 bpm. These findings confirm first‐trimester FHRs cannot predict fetal sex. Sonographers can confidently respond to patient questions during NIPT scans about the lack of relationship between FHR and fetal sex.