O22 MATERNAL AND FETAL OUTCOMES OF VARIOUS ANTIHYPERTENSIVE TREATMENT REGIMENS DURING PREGNANCY: INSIGHTS FROM THE CZECH NATIONAL REGISTRY 2012-2022

Introduction: Arterial hypertension affects about 5-10% of pregnancies and has detrimental effects on pregnancy outcomes in both the mother and fetus. This study aimed to analyze the outcomes of pregnancy in women treated with different antihypertensive drugs. Methodology: Nationwide data on all births and abortions in the period 2012-2022 in the Czech Republic were obtained from the National Registry of Reproductive Health (NRRZ) and the National Registry of Reimbursable Health Services (NRHZS). Women who had the diagnosis I10 within one year before pregnancy and were prescribed any antihypertensive drug from selected ATC groups (C02, C03, C07, C08, C09) were classified as pre-existing hypertension. Women diagnosed with O13 or I10 during pregnancy were classified as pregnancy-induced hypertension. Hypoxia in the newborn was defined as pH <7.1 or Apgar score <8 present after delivery. For all factors, univariate logistic regression was used to calculate the odds ratios (OR) of adverse outcomes. Results: There were a total of 1,154,648 deliveries in the 11-year period. 95,215 women (8.2%) had hypertension in pregnancy, out of these 21,094 (22.2%) were treated with antihypertensive drugs. Odds ratios for caesarean section, pre-term delivery, low birth weight, newborn hypoxia, and pre-eclampsia in women using different antihypertensive classes and drugs are shown in the Figure. The risk of maternal and fetal complications was higher with calcium channel blockers (mainly amlodipine) compared to methyldopa and beta-blockers. Among beta-blockers, bisoprolol had the most favorable safety profile. Although used in limited numbers, diuretics, verapamil, ACE-inhibitors and angiotensin receptor blockers (ARBs) appeared to be comparably safe to methyldopa. A combination of multiple antihypertensive drugs was associated with a higher risk of adverse outcomes. Conclusion: Bisoprolol, verapamil, and diuretics seem to have a risk of adverse maternal and fetal outcomes comparable to methyldopa. Amlodipine and multiple antihypertensive drug combinations are associated with increased risk.