From the Guidelines
Dexamethasone should be given to pregnant women at risk of preterm delivery between 34 0/7 and 36 6/7 weeks of gestation, with a high risk of preterm birth within the next 7 days and before 37 weeks of gestation. The standard regimen consists of two doses of 12 mg of intramuscular betamethasone 24 hours apart, as recommended by the Society for Maternal-Fetal Medicine 1. This treatment has been shown to decrease the composite outcome of need for respiratory support and severe respiratory morbidity in newborns 1.
Key Considerations
- The primary goal of antenatal corticosteroid administration is to reduce neonatal morbidity, particularly respiratory distress syndrome, intraventricular hemorrhage, and necrotizing enterocolitis 1.
- The optimal benefit of antenatal corticosteroids occurs when delivery happens at least 24 hours after the first dose and within 7 days of treatment initiation 1.
- The protective effects of antenatal corticosteroids gradually diminish after 7 days, though some benefit may persist for up to 14 days after administration 1.
Special Populations
- Consideration for the use of antenatal corticosteroids may be given to select populations not included in the original Antenatal Late Preterm Steroids trial, such as patients with multiple gestations reduced to a singleton gestation on or after 14 0/7 weeks of gestation, patients with fetal anomalies, or those who are expected to deliver in <12 hours 1.
- Antenatal corticosteroids are not recommended for fetal lung maturity in pregnant patients with a low likelihood of delivery before 37 weeks of gestation, or in patients with pregestational diabetes mellitus due to the risk of worsening neonatal hypoglycemia 1.
From the Research
Dexamethasone Administration for Preterm Labor
- Dexamethasone is administered to women at risk of preterm birth to reduce the incidence of respiratory distress syndrome (RDS), necrotizing enterocolitis, and intraventricular hemorrhage in preterm babies 2, 3, 4.
- The optimal dose of dexamethasone is still a topic of debate, with studies comparing different regimens such as 5-mg and 6-mg doses 3 and 6-mg and 8-mg doses 5.
- A study found that a 5-mg dose of dexamethasone is noninferior to a 6-mg dose in preventing neonatal respiratory distress syndrome in preterm births 3.
- Another study compared oral and intramuscular administration of dexamethasone and found that oral administration increases neonatal morbidity without demonstrable benefit 5.
- Antenatal corticosteroids, including dexamethasone, have been shown to reduce the risk of neonatal death, RDS, cerebroventricular hemorrhage, and necrotizing enterocolitis 4.
Timing of Dexamethasone Administration
- Dexamethasone can be administered to women at risk of preterm birth between 24 and 37 weeks of gestation 4, 6.
- A study found that antenatal betamethasone administered to women at risk of preterm birth between 24 and less than 37 weeks of gestation reduces the incidence of respiratory distress syndrome 6.
- The optimal time to deliver the course of corticosteroids is not well established, but it is generally recommended to administer the course as soon as possible after preterm labor is diagnosed 4.