What are the guidelines for steroid use in pregnant women?

Steroid Use in Pregnant Women

Administer betamethasone 12 mg intramuscularly, two doses 24 hours apart, to all pregnant women between 24+0 and 33+6 weeks of gestation who are at high risk of preterm delivery within 7 days to reduce neonatal mortality and respiratory morbidity. 1

Antenatal Corticosteroids for Fetal Lung Maturation

Primary Indication: Early Preterm Birth (24-34 weeks)

• Give betamethasone 12 mg IM × 2 doses, 24 hours apart, for women at 24+0 to 33+6 weeks with anticipated delivery within 7 days 1, 2
• Specific high-risk scenarios include: preterm labor with cervical dilation ≥3 cm or 75% effacement, spontaneous rupture of membranes, or planned preterm delivery for maternal/fetal indications (preeclampsia, fetal growth restriction, oligohydramnios) 1
• Administer steroids even if delivery is expected within 18 hours—the benefit persists despite suboptimal timing 2
• The primary benefit is reduction in neonatal mortality, respiratory distress syndrome, and intraventricular hemorrhage 1, 2

Late Preterm Birth (34-36 weeks)

• Consider betamethasone only if delivery is highly likely within 7 days and before 37 weeks 1, 3
• The benefit here is primarily reduction in transient tachypnea of the newborn, a self-limited condition 3
• Diabetes mellitus is an absolute contraindication for late preterm steroids due to increased risk of severe neonatal hypoglycemia 1
• Do not use steroids routinely for elective cesarean delivery at term 4

Rescue Dosing

• Give one additional rescue course if the initial course was >14 days ago, gestational age remains ≤34 weeks, and delivery is now imminent 4
• Avoid repeated rescue courses beyond one additional dose—they reduce infant birthweight and head circumference 4

Critical Timing Considerations for Pre-eclampsia

• For women with pre-eclampsia at ≤34 weeks, give corticosteroids if delivery is anticipated within 7 days 4
• For gestational hypertension at ≤34 weeks, give steroids only if delivery is planned within 7 days 4
• Do not give steroids for HELLP syndrome specifically—six guidelines explicitly recommend against this 4

Steroids for Maternal Medical Conditions During Pregnancy

Chronic Disease Management

• Continue azathioprine, cyclosporine, tacrolimus, and prednisolone in pregnant transplant recipients—do not stop these medications 4
• Stop mycophenolate mofetil at least 12 weeks before conception due to teratogenicity (49% miscarriage rate, 23% structural anomalies) 4
• For rheumatic diseases, continue low-dose prednisone if needed for disease control 1

Respiratory Conditions

• Continue nasal corticosteroids (budesonide, fluticasone, mometasone) at recommended doses throughout pregnancy for chronic rhinitis 1
• Budesonide intranasal is preferred if starting new therapy (FDA category B with extensive safety data) 1
• Short courses of oral corticosteroids can be used after the first trimester for severe asthma exacerbations that threaten maternal respiratory status 1

Key Distinction: Fluorinated vs. Non-Fluorinated Steroids

• For maternal indications, always use prednisone or prednisolone—never dexamethasone or betamethasone 5
• Non-fluorinated steroids (prednisone, prednisolone) are 90% metabolized by placental enzymes before reaching the fetus 5
• Fluorinated steroids (dexamethasone, betamethasone) cross the placenta extensively and expose the fetus to full maternal doses 5
• The only maternal exception: dexamethasone 4 mg daily for fetal first- or second-degree heart block with anti-Ro/SSA or anti-La/SSB antibodies 5

Maternal and Fetal Risks

Maternal Side Effects

• Monitor for hyperglycemia and gestational diabetes—screen all women on glucocorticoids for GDM 4
• Watch for hypertension and increased preeclampsia risk, especially with cyclosporine and tacrolimus 4
• Women taking >5 mg prednisolone daily for >3 weeks are at risk for adrenal suppression—consider stress-dose steroids at delivery and for intercurrent illness, vomiting, or hyperemesis 4

Fetal and Neonatal Risks

• Slight increase in cleft lip with or without cleft palate with first-trimester exposure (though recent data are more reassuring than older studies) 4, 1, 6
• Increased incidence of preterm birth and low birthweight 1, 7
• Neonatal hypoglycemia, especially with late preterm steroids and in preterm/low birthweight infants when administered close to delivery 1, 6
• Only 10% of maternal corticosteroid dose reaches the developing fetus with non-fluorinated steroids 4

Breastfeeding Compatibility

• Oral corticosteroids are compatible with breastfeeding 1
• Prednisone or non-fluorinated steroids <20 mg per day are safe during lactation 1
• Very little corticosteroid enters breast milk 1, 7

Common Pitfalls to Avoid

• Do not give antenatal corticosteroids "just in case"—reserve for women with genuine risk of delivery within 7 days 2
• Do not use dexamethasone or betamethasone for maternal disease control—these expose the fetus unnecessarily 5
• Do not give multiple rescue courses—one additional course maximum 4
• Do not give steroids for HELLP syndrome unless it's for standard fetal lung maturation indications 4
• Do not use late preterm steroids in diabetic women—the risk of severe neonatal hypoglycemia outweighs the modest benefit 1
• Do not continue dexamethasone beyond several weeks for fetal heart block, and never use for complete (third-degree) heart block 5

Monitoring Requirements

• Screen for gestational diabetes in all women receiving glucocorticoids 4
• Monitor blood pressure closely in women on cyclosporine or tacrolimus throughout pregnancy 4
• Observe infants born to mothers on corticosteroids for signs of hypoadrenalism 6
• Consider intramuscular or parenteral glucocorticoid replacement if severe hyperemesis or intercurrent infection develops 4