03/06/07
Premature infants delivered between 28 and 32 weeks are not harmed by a treatment no longer used to help their lungs mature before birth, according to findings of a study in this month’s issue of Pediatrics. Even though previous observational studies suggested that repeated courses of steroids in the womb could result in brain damage, this study shows that the infants’ brains are virtually unaffected.
“The consensus in recent years has been to no longer give women in preterm labor more than one course of steroids because of possible adverse effects, but it means more babies are born needing ventilation,” said Sanjiv Amin, MD, assistant professor of Pediatrics at the University of Rochester Medical center and author of the study. “These findings may give us back a tool to help give these fragile babies a better chance of survival.”
Before concerns arose in 2000 about safety of multiple courses of steroids, many mothers in on-and-off preterm labor received several rounds before delivering. Now, when mothers go into preterm labor, obstetricians will often administer only a single course of steroids to help strengthen the babys’ lungs upon birth. But if the birth is successfully held off for more than 7 days, the mother does not receive another course of medication and the babys’ lungs might not be protected.
This is regrettable, said the study, because one of the biggest challenges for infants born preterm is breathing on their own. Many develop respiratory distress syndrome and receive medications and supplemental oxygen, which can cause problems. Some infants develop bronchopulmonary dysplasia, and others can begin to leak air through the lungs and into the body cavity. Any of these complications, especially coupled with an infection, can be life threatening.
Previous studies showed neurological complications from multiple courses of dexamethasone, a steroid prepared with sulfur. However, clinicians do not commonly use that steroid anymore and have largely switched to sulfur-free steroids, such as betamethasone. This study was based on infants who received betamethasone prior to birth, and they did not show the same adverse effects as previous studies with dexamethasone.
“Perhaps these babies didn’t react the same way as in other studies because the timing of brain maturation is different. It could also be because these babies received a different kind of steroid that did not contain sulfur,” Amin said. “Preliminarily, it looks like we might be able to use multiple courses of steroids, but we need to do more studies to make sure the treatment is safe and effective."
