Comparative study of intravenous hydralazine and labetalol in severe hypertensive disorders of pregnancy


  • Anupma Kumari Department of Obstetrics and Gynecology, N. M. C. H., Patna, Bihar, India
  • Renu Rohatgi Department of Obstetrics and Gynecology, N. M. C. H., Patna, Bihar, India
  • Amrita Singh Department of Obstetrics and Gynecology, L. H. M. C., New Delhi, India
  • Raj Kumar Department of Orthopaedics, RIMS, Ranchi, Jharkhand, India



Hydralazine, Hypertensive disorders of pregnancy, Labetalol, Mean arterial blood pressures


Background: Hypertensive disorders of pregnancy are among the most common medical complications of pregnancy and major cause of maternal, fetal and neonatal morbidity and mortality. The purpose of this study was to compare the efficacy and safety of intravenous hydralazine and labetalol for management of severe hypertensive disorders of pregnancy.

Methods: This prospective study was conducted among 100 women admitted with SBP ≥ 160 or DBP ≥ 110 mmHg or both. Patients were divided into 2 groups randomly: labetalol and hydralazine group.

Results: Majority of patients (38%) were in the age group of 21-25 years and primigravida (52%). There was more significant decrease in the systolic, diastolic and mean arterial blood pressure at the end of 15 and 30 minutes in labetalol group. Labetalol required fewer doses as compared to hydralazine to achieve the target blood pressure (average 1.95 versus 3.1). Total numbers of term deliveries were 19 (38%) in hydralazine group and 16 (32%) in labetalol group. Pre-term deliveries in hydralazine and labetalol group were 14 (28%) and 15 (30%) respectively. Headache was significantly more common in hydralazine treated patients than labetalol group.

Conclusions: Both hydralazine and labetalol were effective and well-tolerated in the treatment of severe hypertensive disorders of pregnancy. Labetalol may be preferred because it was more effective in lowering the systolic blood pressure, diastolic blood pressure and mean arterial pressure to achieve target levels with less number of doses.


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