From the Guidelines
Labetalol, methyldopa, and nifedipine are the safest antihypertensive medications to use during pregnancy, as they have established safety records and minimal risk to the developing fetus. For women with chronic hypertension or who develop hypertension during pregnancy, methyldopa is often the first-line choice at a typical dose of 250-500 mg twice daily, which can be increased as needed 1. Labetalol is another excellent option, usually started at 100-200 mg twice daily and titrated up as necessary. Extended-release nifedipine (30-60 mg daily) is a suitable calcium channel blocker alternative.
Key Considerations
- ACE inhibitors, ARBs, and direct renin inhibitors should be strictly avoided during pregnancy as they can cause fetal kidney damage, growth restriction, and other serious complications 1.
- Blood pressure goals during pregnancy are typically less aggressive than in non-pregnant patients, with targets generally below 150/100 mmHg 1.
- Regular monitoring of blood pressure and fetal growth is essential throughout pregnancy for women taking these medications 1.
Medication Options
- Labetalol: 100-200 mg twice daily, titrated up as necessary 1.
- Methyldopa: 250-500 mg twice daily, increased as needed 1.
- Extended-release nifedipine: 30-60 mg daily 1.
Important Notes
- The most recent and highest quality study, published in 2020, recommends labetalol and nifedipine as first-line treatment for hypertensive emergencies during pregnancy 1.
- Methyldopa should not be used primarily for urgent BP reduction 1.
- Magnesium sulfate is recommended for the prevention of eclampsia and treatment of seizures, but should not be given concomitantly with calcium channel blockers due to the risk of hypotension 1.
From the FDA Drug Label
Pregnancy Teratogenic Effects. Reproduction studies performed with methyldopa at oral doses up to 1000 mg/kg in mice, 200 mg/kg in rabbits and 100 mg/kg in rats revealed no evidence of harm to the fetus. Published reports of the use of methyldopa during all trimesters indicate that if this drug is used during pregnancy the possibility of fetal harm appears remote. In five studies, three of which were controlled, involving 332 pregnant hypertensive women, treatment with methyldopa was associated with an improved fetal outcome
Methyldopa is considered safe for use in pregnancy, as studies have shown no evidence of harm to the fetus and improved fetal outcomes in pregnant hypertensive women 2.
- Key points:
- No evidence of harm to the fetus in animal studies
- Improved fetal outcomes in pregnant hypertensive women
- Possibility of fetal harm appears remote Note that while methyldopa appears to be safe, it should only be used during pregnancy if clearly needed.
From the Research
Hypertension Medication Safe for Pregnancy
- The following medications are considered safe for use during pregnancy:
- These medications are recommended for the treatment of hypertension in pregnancy due to their efficacy and safety profiles 3, 4, 5, 6, 7
Efficacy of Medications
- A study comparing the efficacy of nifedipine, labetalol, and methyldopa found that nifedipine resulted in a greater frequency of primary outcome attainment than labetalol or methyldopa 3
- Another study found that labetalol was the most frequently used medication for treating hypertension in pregnancy, followed by nifedipine and hydralazine 4
- A systematic review found that oral nifedipine, labetalol, and methyldopa are suitable options for treating severe hypertension in pregnancy and postpartum 7
Safety of Medications
- The medications mentioned above have been found to be safe for use during pregnancy, with no significant differences in adverse maternal or fetal outcomes 3, 4, 7
- A review of pharmacokinetics found that there is no fetal accumulation of methyldopa, labetalol, or nifedipine, and that the medications do not pose a significant risk to the fetus 6