Role of Autonomic Nervous System in Hemodynamic Adaptations in Mid-trimester pregnant women

Pregnancy is biggest physiological challenge in a woman’s life that necessitates cardiovascular adjustment to meet metabolic demands from the growing fetus. Multiple factors contribute to this physiologic hemodynamic alterations, of which Autonomic nervous control plays a vital role, derangement of which ends up in PIH .We aimed to study the adaptation in autonomic control during normal pregnancy especially in midtrimesterprimi based on heart rate variability(HRV) and compared with age matched nonpregnant women. Following Institutional Ethical clearance, Electrocardiogram (ECG) lead II was acquired from 30 mid trimester primi women using RMS polyrite 2.2 in supine rest and one minute controlled deep breathing. HRV parameters such as Time and Frequency Domain measures were analysed using Finland Software 2.1. Statistical Results were taken as significant for p<0.05. Our study showed reduced HRV with significant parasympathetic withdrawal and sympathetic overdrive, an indispensable physiological adaptation. Key word: Pregnancy, Midtrimester, Autonomic Nervous System, Heart Rate Variability