Giving mothers injections of corticosteroids within a week of giving birth reduces a substantial risk that infants born at 23 to 25 weeks of gestation will die or experience neurodevelopmental impairment, new research has found.
Although mothers experiencing preterm labor at less than 35 weeks of gestation are currently given corticosteroid therapy to improve infant lung maturity, decrease neonatal problems, and reduce infant death, there has been a lack of data to establish whether such therapy improves outcomes for preterm infants born at weeks 22 to 25 of gestation. Now, research findings appearing today in JAMA indicate that corticosteroid therapy is associated with a reduction in death or neurodevelopmental impairment for infants born at weeks 23 to 25, but not at week 22, of gestation.
The study involved 4924 very preterm infants delivered at 25 weeks or less who were born in 1993 through 2009 and followed up for 18 to 22 months. Although the therapy improved outcomes, the researchers also noted the treatment offers only limited protection, reducing the percentage of preterm infants who died or lived with neurodevelopmental impairment at 18 to 22 months from 81.5% among those whose mothers were not treated to 64.2% among infants whose mothers received therapy.
Waldemar A. Carlo, MD, lead author and director of the division of neonatology at the University of Alabama at Birmingham, discusses his team’s findings:
“We did the study because there is a current controversy about how early antenatal corticosteroid therapy is effective in pregnancy. The current literature suggests that at 26 weeks and beyond the benefits are apparent. The current recommendation is to use as early as 24 weeks, but there have been no randomized trials for infants born at 24 or 25 weeks and there are very limited data on long-term outcomes.
“We found that at 23, 24, and 25 weeks, there were consistent effects and benefits in corticosteroid therapy in major outcome measures, including death and neurodevelopment, and there is substantial literature from randomized controlled trials that there are no adverse effects on the mother.
“This study is a game changer because it shows increased survival and less impairment. At 23 weeks, you have almost twice as many healthy babies surviving. If you look at the numbers needed to treat, corticosteroid therapy saves 1 life for every 5 treated, which is very good. But also remember, that the impact for survival is still low overall. It’s not like corticosteroid therapy is a cure for all babies.
“We did not make a recommendation to lower the therapy threshold because to do so, you need a randomized controlled trial to confirm our findings. Such a trial is unlikely to be done because it would be so expensive to do, and given that the randomized controlled trials of 26 weeks and above show benefits and this study shows benefits, it’s a matter of where people want to put their money.”