Prenatal maternal distress and fetal heart rate: Examining sex-specific sensitivity

Fetal heart rate is linked to fetal well-being and later neurodevelopmental outcomes. Prenatal maternal psychological distress may influence fetal heart rate through physiological changes in utero. However, few studies have examined how maternal distress relates to fetal heart rate, or whether these associations differ by fetal sex. We hypothesized that prenatal maternal depressive and anxiety symptoms and emotion dysregulation would associate with higher fetal heart rate and lower variability, with stronger effects among males. Participants were 159 third-trimester mothers, with a range of scores on emotion dysregulation. Exclusion criteria included substance use, gestational diabetes, pre-eclampsia, and twin pregnancies. Twenty minutes of fetal heart rate data were collected remotely. Depressive and anxiety symptoms, and emotion dysregulation were self-reported via questionnaires. Higher maternal anxiety was related to higher fetal heart rate for males, but not females. We found no interactions with fetal sex for depressive symptoms or emotion dysregulation. Higher symptoms of depression and anxiety predicted lower fetal heart rate variability, but there were no significant interactions with fetal sex. Prenatal maternal distress has differential effects on fetal heart rate and heart rate variability. Fetal heart rate also varied by sex in relation to maternal anxiety, suggesting that sex-specific factors and anxiety-related physiological changes may uniquely influence fetal development. Clinically, this underscores the importance of screening for and addressing prenatal maternal mental health, with potential benefits for both maternal and fetal well-being.