Prehypertension During Pregnancy as a Risk Factor for Adverse Perinatal Outcome: A Historical Cohort Study [30L

Abstract

INTRODUCTION: Hypertension during pregnancy is an important cause of perinatal morbidity and mortality. Prehypertension has been linked to cardiovascular morbidity in non-pregnant women. The objective of this study was to assess the association between prehypertension and adverse perinatal outcomes in apparently healthy women. METHODS: Historical cohort study. SETTING: High complexity institutions located in Bogotá, Colombia. POPULATION: Women with less than 20 weeks of gestation, single live fetus, with two or more abnormal blood pressure measurements (systolic 120-139 mmHg/diastolic 80-89 mmHg) six hours apart. Patients with prior diseases, assisted reproduction pregnancies, or with a diagnosis of fetal abnormality were excluded. Analysis: Baseline characteristics and pregnancy outcomes were retrieved from the electronic medical record. Gestational age was determined by last menstrual period and confirmed by ultrasound. Exposed and non-exposed cohorts were compared. Exploratory univariate regression analysis and multiple logistic regression were performed, adjusting for the presence of confounding variables. The study protocol was approved by the Ethics Committee of the participating institutions. RESULTS: The two groups were similar in terms of sociodemographic and clinical characteristics. Adjusted and non-adjusted odds ratios with 95% confidence intervals were reported. Controlling for maternal age, education, socioeconomic and civil status, social security, parity, drug abuse and weight gain, it was found that prehypertension was associated with the development of pre-eclampsia (aOR 3.54, 95% CI 1.83–6.83) and hospital admissions during pregnancy (aOR 2.35, 95% CI 1.16–4.76). CONCLUSION: Although women with prehypertension are currently classified as normal, prehypertension in the first half of pregnancy increases the likelihood of adverse perinatal outcomes.