Use of angiotensin II receptor blocker during pregnancy: A case report

BACKGROUND: Drugs that affect the renin-angiotensin system, such as angiotensin II receptor blockers (ARBs) and angiotensin-converting enzyme inhibitors are not typically recommended for pregnant women because of their potential fetal toxicity. CASE STUDY: A 32-year-old pregnant woman with nephrotic syndrome lasting more than 5 years became pregnant for the first time. She had been taking losartan tablets before and during pregnancy. Ultrasound at 24(+2) weeks of pregnancy showed oligohydramnios, and the maximum vertical depth of amniotic fluid volume was 1.4 cm. Follow-up ultrasound examinations every 2 weeks showed persistent oligohydramnios [amniotic fluid volume: 1.1–3.4 cm, amniotic fluid index 1.9–6.9 cm]. B-ultrasound at 30(+2) weeks showed slightly enhanced fetal renal cortex echo. The patient was treated at 32(+2) weeks of pregnancy at our hospital. DIAGNOSES: Nephrotic syndrome and oligohydramnios. INTERVENTIONS: Losartan was discontinued and replaced by nifedipine controlled-release tablets to lower blood pressure. The amount of amniotic fluid gradually increased to normal levels within 8 days. The patient was discharged at 33(+2) weeks of pregnancy for follow-up. At 34(+4) weeks, blood pressure had increased to 177/113 mm Hg and the patient was re-hospitalized with nephrotic syndrome complicated by preeclampsia. Due to progression of severe preeclampsia, elective cesarean section was performed at 35(+3) weeks. After delivery, losartan and nifedipine were prescribed to continue lowering blood pressure. The patient was discharged 4 days after surgery. OUTCOMES: Losartan use was terminated at 32(+2) weeks of pregnancy. Amniotic fluid returned to normal after 8 days and the baby was delivered after 22 days. At last follow-up, the infant was 24 months old and healthy. CONCLUSION: Although ARBs are effective for treating hypertension, they should be replaced by other classes of anti-hypertensive drugs in pregnant women. Pregnant women who elect to continue using ARBs should be informed about risks, they should be carefully monitored during pregnancy, and their pregnancy should be allowed to proceed as long as clinically feasible in order to optimize maternal and infant outcomes.