Betamethasone Dosing for Fetal Lung Maturation

Indications for Betamethasone Administration

The American College of Obstetricians and Gynecologists recommends betamethasone for pregnant women with singleton pregnancies between 34 0/7 and 36 6/7 weeks of gestation who are at high risk of preterm birth within the next 7 days and before 37 weeks of gestation 1
Betamethasone is indicated for women with preterm labor with intact membranes and cervical dilation of 3 cm or 75% cervical effacement, spontaneous rupture of the membranes, or expected preterm delivery for other indications, such as gestational hypertension or preeclampsia 2

Antenatal corticosteroid administration in the late preterm period is associated with decreased need for respiratory support (11.6% vs 14.4%; relative risk [RR], 0.80) and decreased severe respiratory morbidity (8.1% vs 12.1%; RR, 0.67) 2
Betamethasone reduces risks of adverse neonatal complications, including death, respiratory distress syndrome, intraventricular hemorrhage, and sepsis, according to the American College of Obstetricians and Gynecologists 1

The American College of Obstetricians and Gynecologists suggests considering betamethasone for select populations not included in the original ALPS trial, including patients with multiple gestations reduced to a singleton gestation on or after 14 0/7 weeks of gestation, patients with fetal anomalies, and patients expected to deliver in <12 hours 3
Betamethasone should NOT be administered in pregnant patients with a low likelihood of delivery before 37 weeks of gestation or pregnant patients with pregestational diabetes mellitus due to risk of worsening neonatal hypoglycemia 3, 4

Neonatal hypoglycemia is more common with betamethasone administration but is typically mild and self-limited (93% resolve within 24 hours) 4
Long-term neurodevelopmental effects of antenatal corticosteroids remain uncertain, requiring thorough patient counseling about potential risks and benefits, as recommended by the American College of Obstetricians and Gynecologists 4, 5

The American College of Obstetricians and Gynecologists recommends administering betamethasone 12 mg intramuscularly in two separate doses 24 hours apart for fetal lung maturation in pregnancies at risk of preterm labor 6
For singleton pregnancies between 34 0/7 and 36 6/7 weeks with a high risk of delivery within the next 7 days, offer a single course of betamethasone 12 mg IM every 24 hours for 2 doses 6

Do not administer betamethasone to patients with pregestational diabetes mellitus due to the increased risk of severe neonatal hypoglycemia 6
Do not administer betamethasone to patients with a low probability of delivery before 37 weeks to avoid unnecessary exposure 6
Do not administer betamethasone to patients who have already received a prior course in the late preterm period 7, 8

For twin pregnancies less than 34 weeks, administer the standard scheme 7
For twin pregnancies in the late preterm period, the evidence is insufficient; consider on a case-by-case basis with shared decision-making with the patient 7, 8

Do not delay medically indicated delivery to complete the steroid course in the late preterm period 7, 8
If delivery is anticipated in less than 12 hours, still consider administration 6