Stage I hypertension and pregnancy: Scope of disease and pregnancy outcomes

To compare the rates of preeclampsia between obstetric patients with stage I hypertension and those who are normotensive. Secondary aims include identifying risk factors for preeclampsia within the stage I hypertension cohort and comparing the rates of other adverse pregnancy outcomes between cohorts.

We conducted a retrospective cohort study of individuals who delivered from January 1, 2019 to July 31, 2019, at a single academic center. Patients were assigned to cohorts comprised of normotensive pregnant patients and those with stage I hypertension prior to 20 weeks gestation. Stage I hypertension is defined as a systolic blood pressure of 130-139 mmHg, a diastolic blood pressure of 80-89 mmHg, or both. Differences in outcomes were evaluated using t- tests and logistic regression models.

A total of 540 patients were included, 68 of whom were identified as having stage I hypertension. Among patients with stage I hypertension in pregnancy, 19 % developed preeclampsia compared to 10 % of normotensive patients (Odds Ratio (OR) = 2.14; p = 0.028). The odds of gestational diabetes (OR = 2.65, p = 0.01) and gestational hypertension (OR = 7.99, p < 0.001) were also increased in the stage I hypertension cohort. Of the patients with stage I hypertension, a history of gestational diabetes was the only risk factor associated with subsequent development of preeclampsia (OR = 7.95, p = 0.034).

In our cohort, stage I hypertension prior to 20 weeks was associated with a significant increased rate of preeclampsia, gestational hypertension and gestational diabetes compared to normotensive patients.