Impact of Depressive Symptoms during the Second Trimester of Pregnancy on Maternal and Fetal Heart Rate Variability.

Objective: This study explores how maternal depressive symptoms during the second trimester, a critical phase for autonomic nervous system (ANS) development, affect maternal and fetal heart rate variability (HRV) in the third trimester, with implications for infant development. Methods: We examined the effects of second trimester maternal depression on subsequent maternal and fetal HRV. A cohort of women in early or late second trimester completed depression assessments using the Edinburgh Postnatal Depression Scale (EPDS) and underwent HRV evaluations in the third trimester. Results: Among 118 participants, 97 completed the EPDS at 14-20 weeks, with 12 showing depressive symptoms. At 21-28 weeks, 111 participants were assessed, and 24 were identified as possibly depressive. Depressive symptoms were linked to increased maternal pNN50% (percentage of successive NN intervals differing by more than 50 ms) and decreased detrended fluctuation analysis alpha, indicating hemodynamic shifts. Their fetuses showed reduced root mean square of successive differences, standard deviation of successive differences, and short-term and long-term variability indices, suggesting weakened parasympathetic activity. Conclusion: Prenatal depression influences maternal physiological adaptation and fetal ANS development, highlighting HRV as a potential biomarker for predicting neurodevelopment. Early identification and treatment of mid-pregnancy depressive symptoms may help mitigate potential risks to infant neurodevelopment.