From the Guidelines
Pregnant women should avoid medications unless necessary, but methyldopa, labetalol, and long-acting nifedipine are considered safe and effective for managing hypertension during pregnancy. According to the most recent guidelines 1, these medications are recommended for pregnant women with hypertension, as they have been shown to be effective in reducing blood pressure while minimizing the risk of fetal harm.
Key Considerations
- ACE inhibitors, angiotensin receptor blockers, and spironolactone are contraindicated during pregnancy due to the risk of fetal damage 1.
- Diuretics are not recommended for blood pressure management in pregnancy but may be used during late-stage pregnancy if needed for volume management 1.
- The American College of Obstetricians and Gynecologists recommends that postpartum patients with gestational hypertension, preeclampsia, and superimposed preeclampsia have their blood pressures observed for 72 hours in the hospital and for 7-10 days postpartum 1.
Medication Options
- Methyldopa: considered a first-line treatment for hypertension in pregnancy 1.
- Labetalol: also considered a first-line treatment for hypertension in pregnancy 1.
- Long-acting nifedipine: recommended for managing hypertension in pregnancy, particularly in cases where methyldopa and labetalol are not effective or tolerated 1.
Important Notes
- Pregnant women should always consult with their healthcare provider before taking any medication, as individual circumstances may vary and recommendations may change based on trimester and specific health needs.
- Treatment decisions should balance maternal benefit against potential fetal risk, and medications should be used only when necessary and under close medical supervision.
From the FDA Drug Label
Pregnancy:Teratogenic Effects: Pregnancy Category C: Teratogenic studies were performed with labetalol in rats and rabbits at oral doses up to approximately six and four times the maximum recommended human dose (MRHD), respectively. No reproducible evidence of fetal malformations was observed. Increased fetal resorptions were seen in both species at doses approximating the MRHD. Pregnancy Category C In rodents, rabbits and monkeys, nifedipine has been shown to have a variety of embryotoxic, placentotoxic, teratogenic and fetotoxic effects, including stunted fetuses (rats, mice and rabbits), digital anomalies (rats and rabbits), rib deformities (mice), cleft palate (mice), small placentas and underdeveloped chorionic villi (monkeys), embryonic and fetal deaths (rats, mice and rabbits), prolonged pregnancy (rats; not evaluated in other species), and decreased neonatal survival (rats; not evaluated in other species).
Medications for Pregnant Women:
- Labetalol: may be used during pregnancy only if the potential benefit justifies the potential risk to the fetus 2
- Nifedipine: should be used with caution, as it has been shown to have embryotoxic, placentotoxic, teratogenic and fetotoxic effects in animal studies 3 Key Considerations:
- Both labetalol and nifedipine are categorized as Pregnancy Category C, indicating that they should be used with caution during pregnancy.
- There are no adequate and well-controlled studies in pregnant women for either medication.
- Careful monitoring of blood pressure and potential fetal risks is necessary when administering these medications to pregnant women.
From the Research
Prenatal Medications
- The following medications are recommended for pregnant women:
- Iron and folic acid supplementation to prevent anaemia and improve maternal, pregnancy, and infant outcomes 4
- Daily oral iron supplementation to reduce maternal anaemia and iron deficiency at term 4
- Iron + folic acid supplementation to reduce maternal anaemia at term and probably reduce maternal iron deficiency at term 4
- Prenatal supplements containing vitamins A, C, D, K, B1, B3, B5, B6, folate, biotin, and B12 to reduce the risk of pregnancy complications and infant health problems 5
- Supplements with target doses of vitamin A, vitamin D, folate, calcium, iron, and ω-3 FAs to help pregnant women achieve the recommended intake without exceeding upper limits 6
- Micronutrient supplementation, including folate, iron, calcium, vitamin D, and A, to ensure adequate intake of key elements 7
Key Nutrients for Prenatal Supplementation
- Vitamin A: ≥198 mcg retinol activity equivalents of total vitamin A (with ≤2063 mcg preformed retinol) 6
- Vitamin D: 7-91 mcg 6
- Folate: 169-720 mcg dietary folate equivalents of folic acid 6
- Calcium: 383-943 mg 6
- Iron: 13-22 mg 6
- ω-3 FAs: ≥59 mg 6