B AHMED1, D TRAN1, H ZOEGA3, S KENNEDY2, L JORM1, A HAVARD1
1Centre for Big Data Research in Health, University of New South Wales, Sydney, Australia, 2School of Women’s & Children’s Health, University of New South Wales , Sydney, Australia, 3Centre of Public Health Sciences, Faculty of Medicine, University of Iceland, Reykjavik, Iceland
Aims: To explore whether use of renin-angiotensin system (RAS) blockers in early pregnancy is associated with adverse perinatal outcomes.
Background: Previous research that reported adverse perinatal outcomes following first trimester exposure to angiotensin converting enzyme inhibitors (ACEIs), was limited by the use of non-hypertensive women as controls. We examined outcomes of pregnancies with first trimester exposure to RAS blockers, whilst controlling for underlying hypertension.
Methods: Perinatal data for all deliveries in New South Wales, between 2005 and 2012 were linked to hospital discharge and pharmaceutical dispensing records. Analyses were restricted to women who were concessional beneficiaries and had chronic hypertension. Outcomes of interest were preterm delivery, caesarean section, low birth weight (LBW) and small for gestational age (SGA). We used multivariable logistic regression, adjusting for demographics and comorbidity. Pregnancies exposed to ACEIs and angiotensin receptor blockers (ARBs), were compared with pregnancies exposed to methyldopa. We excluded pregnancies if RAS blockers were used beyond first trimester.
Results: There were 456 births to women with chronic hypertension, who received either ACEIs (n=67), ARBs (n=73) or methyldopa (n=316) during first trimester. Compared with pregnancies exposed to methyldopa, the adjusted odds ratio (aOR) for ACEI exposure was 0.5 (95% CI: 0.2 – 1.1) for preterm delivery, 0.6 (0.2 – 1.3) for LBW, 0.8 (0.4 – 1.9) for SGA, and 1.6 (0.8 – 3.1) for caesarean section. The corresponding aORs for ARB exposure were 0.7 (0.3 – 1.5), 1.3 (0.7 – 2.6), 1.2 (0.6-2.6) and 1.2 (0.6 – 2.4).
Conclusion: Adverse perinatal outcomes related to RAS blocker use restricted to first trimester were not observed, however the possibility of an association cannot be ruled out due to limited power.
Sean is a Head of Nephrology at Sydney Children’s Hospital Randwick and senior lecturer in the School of Women’s & Children’s Health,University of New South Wales.