The Effect of Maternal Autonomic Regulation on fetal Hemodynamic Fluctuations and Growth

Objective. The development of fetal autonomic regulation has a crucial influence on fetal hemodynamics. Heart rate variability (HRV) captures the continual changes in sympathetic and parasympathetic balance. The study was focused on the detection of the relationship between maternal HRV, fetal HRV, neonatal biometry, and Apgar score. Methods. This study was performed among 71 pregnant women at 22-36 weeks. Fetal HRV data were collected using non-invasive fetal electrocardiography (NI-FECG) with the “Cardiolab Baby Card” system, which registered RR-intervals from the maternal abdominal wall over 30–60 minutes. Additionally, the study recorded neonatal biometry (birth weight, body length, and head circumference) and the 1-minute Apgar score. Results. Maternal stress index (SI) demonstrated strong or moderate negative correlation with acceleration capacity (AC) maternal (r=-0.71; p .001), deceleration capacity (DC) maternal (r=-0.78; p .001), AC fetal (r=-0.42; p .001), DC fetal (r=-0.37, p=.001), and STV (r=-0.27, p=.022). A positive moderate correlation was found in pairs Apgar score vs AC fetal (r=0.31; p=.009), DC fetal vs Apgar score (r=0.35, p=.003), STV (r=0.27; p=.024), and LTV (r=0.25; p=.038). A negative moderate correlation was detected between the SI fetal and Apgar score (r=-0.27; p=0.02). The multivariate logistic regression detected the relationship between maternal SI and neonatal body weight. Conclusion. Maternal stress-related sympathetic activity is intrinsically linked to fetal autonomic regulation and neonatal outcomes. Utilizing maternal SI as a prognostic marker could provide clinicians with a fundamental tool for developing models to predict fetal growth restriction and ensure timely intervention.