Associations Between Hypertensive Disorders in Pregnancy and Maternal and Fetal Outcomes: A Retrospective Cohort Study on Systolic and Diastolic Blood Pressure Levels at Delivery

Background: This study aimed to determine the effect of hypertensive disorders during pregnancy, systolic blood pressure (SBP), and diastolic blood pressure (DBP) on maternal and fetal mortality and morbidity. Methods: This retrospective cohort study included 195 women aged ≥18 years with hypertensive disorders during pregnancy who underwent caesarean section between 2012 and 2017. Patients were divided into groups based on their hypertensive diagnosis (25 with gestational hypertension (GHT), 164 with preeclampsia, 6 with eclampsia) or the recorded SBP or DBP readings at delivery. Logistic regression and linear regression were used to examine associations between hypertensive diagnosis, DBP at delivery, SBP at delivery, and the development of adverse maternal and fetal outcomes after adjusting for confounders. Results: Multivariable regression analysis revealed a trend toward an increased risk of intrauterine growth restriction (IUGR) (adjusted risk ratio (aRR) = 2.92; p = 0.09) in patients with eclampsia compared to those with GHT, while patients with preeclampsia had a significantly increased risk of IUGR (aRR = 2.77; p = 0.003). Patients with preeclampsia also had a threefold increased risk of premature delivery (aRR = 3.29; p < 0.004), while those with eclampsia had a fourfold increased risk (aRR = 4.09; p = 0.002) compared to patients with GHT. Both groups also had significantly lower fetal birth weights than the GHT group. A DBP of ≥90 mmHg during delivery was associated with significantly reduced fetal birth weight (coefficients (Coef.), –381.5, 95% confidence interval (CI), –739.6 to –23.4; p = 0.04). No significant differences were observed in the outcomes between patients with an SBP value <140 mmHg during delivery and those with a SBP recording ≥140 mmHg. Conclusions: SBP and DBP are important parameters in the maternal early warning criteria. Strict DBP monitoring may help to increase patient safety, especially in patients with preeclampsia or eclampsia.