Fetomaternal outcomes among normotensive and stage one Hypertensive patients at Jaramogi Oginga Odinga teaching and Referral hospital: a prospective cohort study

Abstract

Hypertension in pregnancy is a leading cause of adverse maternal and fetal outcomes. Complications associated with hypertension include intrauterine growth restriction (IUGR), premature delivery, poor neonatal scores at birth, prolonged admission, maternal end organ damage and increased operative delivery. Recent studies in non-pregnant subjects indicate that a blood pressure range of 130/80 to 140/90 is associated with significant cardiovascular complications. The American Heart association has consequently recommended that this range be termed stage one hypertension. The effect of this new stage one hypertension has however not been adequately studied in pregnancy. The main objective of this study was to compare the fetomaternal outcomes between normotensive patients and those with stage one hypertension attending antenatal clinic (ANC) at Jaramogi Oginga Odinga Teaching and Referral Hospital (JOOTRH). The hypothesis was that there was no statistically significant difference in the fetomaternal outcomes between normotensive and stage one patients attending ANC at JOOTRH. This was a prospective cohort study, where non-probability consecutive sampling was used to select women with singleton pregnancies presenting for ANC before 20 weeks of gestation. A total of 320 women, 160 in each arm were recruited into the study and followed to delivery. Patients with stage one hypertension were the exposed group and those in the normotensive group were the unexposed. Maternal outcome data included gestational hypertension, pre-eclampsia, eclampsia, and mode of delivery. Fetal outcomes included fetal maturity, birth weight, APGAR scores, admission to newborn unit and fetal demise. The Statistical Package for Social Sciences (SPSS) version 25 software was used for analysis. Both descriptive and analytical statistical procedures were employed in analysis. The independent t test was used to compare the sociodemographic and clinical characteristics between the independent groups. A chi-square test of association was used to compare both maternal and fetal outcomes between the independent groups. Binary logistic regression analysis with interaction effects was used to establish the influence of variables that were found to be significantly different on the maternal and fetal outcomes. The socio- demographic characteristics were comparable between the two groups. Twenty-three patients with stage one hypertension (15.9%) developed gestational hypertension compared to eight (5.5%) in the normotensive group (RR 3.23, P value 0.02).Seventeen per cent of the neonates born to patients with stage one hypertension were admitted to the newborn unit compared to ten per cent of those in the normotensive group (RR of 1.98, P value 0.045).Thirty per cent of the neonates born to patients in the stage one hypertensive group scored below 7 on the APGAR score at one minute compared to twenty per cent in the normotensive group (P value 0.04). There was no statistically significant difference in the other maternal and fetal outcomes. In conclusion, patients with stage on hypertension have worse fetal and maternal outcomes than their normotensive counterparts and should be offered a more rigorous antenatal care based on this observed higher risk of fetomaternal complications.