Role of Ambulatory Blood Pressure Monitoring in Predicting Adverse Maternofetal Events in Pregnancy
Authors: Rao Vavilala Satish Kumar , Garre Indrani , Beeram Sumalatha 
Published: April 2021

Aims To correlate the relationship between the ambulatory blood pressure parameters and the occurrence of the antenatal and postnatal adverse maternofetal events in pregnancy.

Methods Observational study designed for 50 pregnant patients who had an appointment to the obstetrics with abnormal blood pressure (BP) measurements and for whom ambulatory blood pressure monitoring (ABPM) was studied between January 2019 and June 2019. Data about age, personal history, obstetrics, family, body mass index (BMI), weight gain in pregnancy, values of blood pressure in the appointment, values recorded in ABPM, delivery and newborn, pregnancy and postpartum events, and follow-up of woman and child. Data were analyzed using descriptive and inferential statistics with Minitab 17.0 for Windows.

Results Patients demographic data, clinical history, and laboratory results, including the ABPM parameters, were compiled. Antenatal complications occurred in 22 patients (44%), and postpartum complications were found in 41 patients (82%) whose ABPM values were deranged. Antenatal complications were studied using the binary logistic regression analysis for calculating the role each factor played in the development of hypertension. In the sample studied, mean age was 24.980 with a standard deviation of 4.876 (p = 0.003; minimum age of 19 years and maximum age of 38 years), mean weight of patient was 63.71 with a standard deviation of 63.71 (p = 0.001), mean gravida was 1.780 with a standard deviation of 0.910 (p = 0.034), mean gestation weeks at presentation was 33.000 weeks with a standard deviation of 4.086 (p = 0.041), mean birth weight was 2.226 with a standard deviation of 0.797 (p = 0.000), mean maximum diastole was 109.22 with a standard deviation of 16.53 (p = 0.002), mean day maximum systole was 187.2 with a standard deviation of 203.5 (p = 0.009), mean day minimum diastole was 63.50 with a standard deviation of 12.99 (p = 0.013), all of which had statistical significance. It is found that the nighttime diastolic blood pressure (DBP) and daytime maximum systolic blood pressure (SBP) were the best predictors of adverse events. Among antenatal complications (ANC), the most common complication is intrauterine growth restriction (IUGR), noted in (n = 19, 86.36%) preterm delivery (n = 17, 77.27%) among the 17 babies who were delivered preterm; 12 (70.5%) needed neonatal intensive care unit (NICU) care of which 4 (25%) babies died because of prematurity; intrauterine death (IUD) was noted in 7 (31.81%) patients and eclampsia was seen in 5 (22.72%). Nondippers proðle had a worse survival rate at follow-up until delivery compared with those with a dipper proðle. Postnatal complications were seen in 41 patients; among them, 13 patients (31.7%) had abnormal fundus examination, 15 patients (36.58%) required usage of antihypertensive beyond first postpartum, 9 patients (21.95%) required blood transfusion for severe bleeding in the form of postpartum hemorrhage. Binary logistic regression for systolic dippers versus nondippers shows statistical significance in age (p = 0.023), weight (p = 0.038), and para (p = 0.045) (Table 3). Binary logistic regression for diastolic dippers versus nondippers shows statistical significance in age (p = 0.039), weight (p = 0.020), birth weight (p = 0.010), maximum heart rate (p = 0.043), and ANC (p = 0.007) Adverse events occurred most commonly in nondippers. Systole nondippers is noted in (n = 41, 82%). Dippers is noted in (n = 9, 18%), Diastole nondippers is noted in (n = 39, 78%) Dippers is noted in (n = 11, 22%).

Conclusion ABPM recorded blood pressure is very precise. ABPM is the advised method for both diagnostic and therapeutic monitoring of hypertensive pregnancy diseases, mainly in situations like whitecoat hypertension, masked hypertension, nocturnal hypertension, and nondipping profile. In patients with high-risk pregnancy, elderly primigravida, and precious pregnancy, who have a high-risk of developing pregnancy-induced hypertension (PIH) and related complications, early use of ABPM predicts adverse maternofetal events, which when intervened at an earlier date can prevent antenatal and postnatal complications.