Background: Blood pressure dysfunctions are one of the biggest complications and causes of maternal mortality during pregnancy. The aim of the present study is to evaluate some of the clinical and demographic risk factors in various aspects, both of which can help to better understand the causes and reduce the incidence of preeclampsia. Method: This nested case-control study was carried out on 270 pregnant women with preeclampsia as the case group and 270 pregnant women who did not have symptoms of preeclampsia at the time of referral were interviewed according to inclusion criteria as the control group. The factors studied included age, body mass index, history of hypertension in mother, history of diabetes in mother, history of lupus in mother, number of pregnancies, history of preeclampsia in previous pregnancies, twin or more pregnancies, season of occurrence, maternal educational level, maternal blood group, maternal occupation status, infant's sex and smoking status which were compared etween the two groups. t test and Chi-square tests were used to compare the variables in both groups. Fisher's exact test or Mann-Whitney U test was used if necessary. Findings: Of the 6929 pregnant women who participated in our study, 541 (7.8%) had preeclampsia. The means of body mass index (BMI) (24.86% versus 23.52%) (P = 0.032), the history of hypertension (19.3% versus 10.7%) (P = 0.006), history of preeclampsia in previous pregnancies (60.2% versus 13.3%) (P < 0.001), low level of education and illiteracy (51.1% versus 39.6%) (P = 0.028), and twin or more pregnancies (5.6% versus 2.2%) (P = 0.045) were significantly higher in the case group when compared to the control group. There was no statistically significant difference between the mean and standard deviation of age and number of pregnancies and the frequency of diabetes and lupus, the frequency of maternal occupation, maternal smoking, maternal blood group, and season of occurrence in the two groups (P > 0.05). Conclusion: Maternal BMI, maternal hypertension, history of preeclampsia in previous pregnancies, low maternal educational status, and twin or multiple pregnancies might be the risk factors for preeclampsia during pregnancy.
Keywords: Preeclampsia; pregnancy; risk factor.