Is Use of Multiple Antihypertensive Agents to Achieve Blood Pressure Control Associated with Adverse Pregnancy Outcomes?

OBJECTIVE: We assessed whether requiring >1 medication for blood pressure control is associated with adverse pregnancy outcomes. STUDY DESIGN: Retrospective cohort of 974 singletons with chronic hypertension at a tertiary care center. Subjects on >1 antihypertensive agent were compared to those on 1 agent < 20 weeks gestational age with results stratified by average blood pressure (<140/90 and ≥140/90 mmHg) from prenatal visits. The primary maternal outcome was preeclampsia; the primary neonatal outcome was small for gestational age (<10(th) percentile). RESULT: Among women with blood pressure ≥140/90 mmHg, women on multiple agents had the greatest risk of preeclampsia, severe preeclampsia, antenatal admissions to rule out preeclampsia, preterm birth < 35 weeks and composite neonatal adverse outcomes. CONCLUSION: Compared to use of a single agent when blood pressure is ≥140/90 mmHg, use of multiple agents increases adverse risks, while no such finding exists when blood pressure is controlled below 140/90 mmHg.