Samira Erfan - General Practitioner, Yazd Cardiovascular Research Center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
Azizeh Ghane Ezzabadi - Diabetes Research Center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
Faezeh Dehghani-Tafti - Fellowship of Echocardiography, Yazd Cardiovascular Research Center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
Masood Rahmanian - Diabetes Research Center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
Mohammad Shafiee - General Practitioner, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
Mohammad Hosein Ahmadieh - Department of Statistic and Epidemiology, School of Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
Seyed Kazem Razavi Ratki - Department of Radiology, Faculty of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
Nasim Namiranian - Assistant professor of Community Medicine, Diabetes Research Center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
Seyed-Mostafa Seyed Hosseini - Assistant Professor of Cardiology, Yazd Cardiovascular Research Center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran

Background: Gestational diabetes [GDM] is one of the most common metabolic disorders associated with many adverse maternal and fetal complications including cardiovascular events. This study aimed to evaluate the function of the autonomic nervous system by heart rate variability [HRV] between pregnant women with GDM and healthy pregnant women. Methods: The study was a case-control observational study on ۵۰ pregnant women with GDM and ۵۱ healthy pregnant women. They were assigned to the study at ۳۲-۳۶ weeks of gestational age. Demographic and past medical history and lab findings were gathered. HRV was assessed by a time-domain analysis of ۲۴-hour cardiac Holter monitoring including SDNN-SDANN-rMSSD and pNN۵۰ variables. Results: The mean age of the participants was ۲۸.۶۹ [± ۵.۵]. Data analysis showed no significant difference in the age [p-value: ۰.۱۰], maternal hypothyroidism [p-value: ۰.۲], and PCO [p-value: ۱/۰۰۰] between two groups. There was no significant difference between SDNN [p-value: ۰.۲۱], SDANN [p-value: ۰.۱۱], and rMSSD [p-value: ۰.۸۷] between two groups. pNN۵۰ in GDM group decreased significantly [P-value = ۰.۰۰۰۱]. Conclusion: A significant decrease in the pNN۵۰ index in GDM group may be a marker of autonomic dysfunction. Reduced pNN۵۰ could be explained by decreasing parasympathetic activity and sympathetic overcome in pregnancy, especially in pregnancy associated with diabetes, leading to instability of the autonomic nervous system.

Gestational diabetes, Autonomic dysfunction, heart rate variability