Effect of antioxidants on amelioration of high-risk factors inducing hypertensive disorders in pregnancy

Abstract

Background: This is a prospective clinical study based on a large sample gathered from multiple centers in China, subordinating to 10th Five-Year Plan of National Science & Technology Progression. We analyzed the high-risk factors inducing hypertensive disorders in pregnancy (HDP) and estimated the potential effect of anti-oxidants administration, including vitamin C (VC), vitamin E (VE) and Salvia Miltiorrhiza L (SML), a Chinese herb medicine, in amelioration of the high-risk factors in pregnancy.

Methods: From April 2005 to July 2006, 4814 pregnant women from 24 national wide cooperative hospitals were involved in this prospective research. The participants were randomly divided into two groups: 1607 cases were in anti-oxidants group with administration of vitamins and SML; 3207 cases were in control group without any medicine given. Every participant was under monitoring for the morbidity of HDP and the high-risk factors were investigated in HDP cases in each group.

Results: (1) The morbidity of HDP was 3.55% in anti-oxidants group vs. 4.18% in control group. No statistical difference existed between the two groups (P > 0.05). (2) In anti-oxidants group, the HDP morbidities among three subgroups: VC + VE + SML, VC + VE and SML only, were 5.51%, 3.05% and 5% respectively. It showed no statistical difference among three remedies (P > 0.05). (3) The related index of factors affecting HDP showed in intensity sequence as follows: family HDP history > profession > education level > age > body weight. The incidence of HDP in normal population was 3.51%, and the incidence of HDP in high-risk pregnant women (family HDP history, heavy physical labor, low education level (middle school and below), age ≥ 40, body mass index ≥ 24) was 5.84%, which was obviously higher than that in normal population (P < 0.01). In anti-oxidants group, the probability of HDP in women with high-risk factors was 3.81%, which was obviously lower than that in control group with high-risk factors at 7.14% (P < 0.01). (4) In control group, the morbidity of HDP in women with family HDP history (especially with sisters'), heavy physical labor, middle school and below, age ≥ 35 was: 50.00%, 15.22%, 6.33%, 26.28% and 5.75%, respectively, and that in anti-oxidants group was 0, 7.69%, 3.74%, 9.27% and 2.67%, respectively, which was obviously lower than that in control group.

Conclusions: The high-risk factors prone to induce HDP included: family history of HDP, heavy physical labor, low education level, aging and obesity. No impressive effect of anti-oxidants application was found in preventing HDP in general population but the remedy demonstrated positive effect on preventing HDP in pregnant women with high-risk factors.