Do different positions during a non-stress test affect the maternofetal physiological parameters and comfort in pregnant women?

Abstract

A non-stress test (NST) is an essential diagnostic test performed during pregnancy to assess fetal well-being. It is a recording of fetal movements besides fetal heart rate, indicating fetal biophysiological well-being. As maternal physiology is altered in various positions, apt positioning during the NST is essential for accurate results while ensuring maternal comfort. This study aims to evaluate the effect of different maternal positions, left lateral and semi-fowler's, on NST reactivity, maternal blood pressure, heart rate, and comfort in pregnant women while performing the NST. This crossover study evaluated 50 healthy pregnant women between 32 and 40 weeks of gestation with no obstetric complications for the effect of maternal positions on maternofetal physiological parameters and comfort. The NST was performed for 20 min in each position with a washout period of 10 min. The maternofetal physiological parameters were recorded by a calibrated sphygmomanometer and the electrocardiograph interpretations. The maternal comfort was assessed using a maternal comfort rating scale (MCRS) for each position after the NST. Relevant descriptive and inferential statistics are applied to compute the results. Statistically, there was a significant difference in the mean maternal blood pressure and heart rate between the left lateral and semi-fowler's positions at 0 and 20 min (P = 0.001), whereas within the groups, in the same position at 0 and 20 min, no significant difference was found. There was no significant difference in NST reactivity (P = 0.79) in different positions. There was no significant difference between the MCR scores of women in either of the positions (Z = -1.64, df = 49, P = 0.100). Semi-fowler's position demonstrated favorable maternal blood pressure and heart rate during the NST in the third trimester of pregnancy, though it was clinically not significant. There was no significant difference in the comfort of women in both positions. Hence, either of the positions can be implemented in practice as an alternative position while performing the NST, based on the women's preference.