Pregnancy and severe chronic hypertension: maternal outcome.

OBJECTIVE: To determine the maternal outcome associated with severe chronic hypertension during the second half of pregnancy.
METHODS: An analysis of data obtained of women with severe chronic hypertension (> or = 160/110 mm Hg) and > or = 20 weeks' gestation who were hospitalized and delivered during a 5-year period. The pregnancy outcome data were collected retrospectively from medical records. Each patient was observed closely throughout hospitalization with intensive monitoring of the clinical status of both mother and fetus. Antihypertensive drugs were used for systolic or diastolic blood pressure > or = 160 and > or = 110 mm Hg, respectively. Women with superimposed preeclampsia received magnesium sulfate. The main outcome measures were peak of blood pressure, superimposed preeclampsia, and major maternal complications.
RESULTS: Of 154 women studied, 111 (72%) had pregestational chronic hypertension, and 120 (78%) developed superimposed preeclampsia. The mean weeks' gestation was 34.5 +/- 4.6. Overall, 110 (71.4%) pregnancies were delivered by cesarean section. Maternal age and parity were significantly higher among women who had pregestational chronic hypertension than those who had chronic hypertension diagnosed during the first half of pregnancy. Abruptio placentae (8.4%), HELLP syndrome (8.4%), acute renal insufficiency (3.9%), pulmonary edema (1.3%), and postpartum hypertensive encephalopathy (1.3%) were the most frequent maternal complications. There were no maternal deaths, disseminated intravascular coagulation, or eclampsia.
CONCLUSION: Three-quarters of women with severe chronic hypertension in the second half of pregnancy developed superimposed preeclampsia. Intensive monitoring of the clinical status of the mother was associated with low maternal morbidity and the absence of maternal deaths. Pregestational chronic hypertension does not change the maternal prognosis.