Effects of yoga on cardiometabolic risks and fetomaternal outcomes are associated with serum nitric oxide in gestational hypertension: a randomized control trial

Abstract

Gestational hypertension (GH) is associated with adverse cardiometabolic and pregnancy outcomes. Though yoga is known to be beneficial in pregnancy, the effects of yoga rendered for twenty weeks starting from 16th week of gestation in pregnant women having risk of GH on the incidence of hypertension, cardiometabolic risks and fetomaternal outcomes have not been studied. A randomized control trial was conducted on 234 pregnant women having risk of GH receiving standard antenatal care (Control group, n = 113), and receiving standard care + yoga (Study group, n = 121). Interventions were given for twenty weeks starting at 16th week of gestation. Baroreflex sensitivity (BRS), heart rate variability (HRV), insulin resistance, lipid-risk factors, and markers of inflammation, oxidative stress and vascular endothelial dysfunction (VED) were assessed before and after intervention. Incidence of new-onset hypertension, level of cardiometabolic risks at 36th week, and fetomaternal-neonatal outcomes in the perinatal period, were noted. The link of hypertension, pregnancy outcomes and cardiometabolic risks with nitric oxide (NO), the marker of VED was assessed by analysis of covariance, Pearson's correlations, and multilinear and logistic regressions. In study group, 6.61% women developed hypertension compared to 38.1% in the control group following 20-week intervention and there was significant decrease in risk of developing GH (RR, 2.65; CI 1.42-4.95). There was less-painful delivery, decreased duration of labor, increased neonatal birthweight and Apgar score in study group. Increase in total power of HRV (β = 0.187, p = 0.024), BRS (β = 0.305, p < 0.001), and decrease in interleukin-6 (β = - 0.194, p = 0.022) had significant association with increased NO. Twenty weeks of practice of yoga during pregnancy decreases the incidence of hypertension, improves fetomaternal outcomes, and reduces cardiometabolic risks in pregnant women having risk of GH. Decreased blood pressure, increased HRV, BRS and birth weight and decreased inflammation were associated with improved endothelial function. Trial registration: Clinical Trials Registry of India (CTRI), registration number: CTRI/2017/11/010608, on 23.11.2017.

Figure 1

RCT consort chart.

Figure 2

Tadasana.

Figure 3

Utkatasana.

Figure 4

Virabhadrasana.

Figure 5

Trikonasana (Modified).

Figure 6

Titilasana.

Figure 7

Vakrasana.

Figure 8

Marjariasana.

Figure 9

Uthita Padasana (modified).

Figure 10

Sukhasana.

Figure 11

Anulom-Vilom or Nadisodhana pranayama.

Figure 12

Chandranadi or left-nostril pranayama.

Figure 13

Bhramari or humming-bee pranayama.

Figure 14

Sheetali or cooling pranayama.

Figure 15

Relaxation in lateral posture.

Figure 16

Comparison of MAP (A), LF-HF ratio (B), BRS (C), TP (D), IL-6 (E) and NO (F) in control and study groups before and after intervention. Results are shown as Mean ± SD. There was no significant difference in any of the parameters between control and study groups before yoga intervention (Pre-Test). Following intervention (Post-Test), MAP, LF-HF ratio and IL-6 were significantly decreased and BRS, TP and NO were significantly increased in the study group compared to the control group. ***p < 0.001.

Figure 17

Pearson correlation of nitric oxide with IL-6 in control group and study group at 36th week of gestation. Blue dots represent control group and orange dots represent study group. NO is negatively correlated with IL-6 in both control and study groups and the correlation is stronger in study group (r = − 0.319, p < 0.001).