Respirator distress syndrome (RDS) is the most common cause of mortality and illness in newborn babies, specifically in those who are born premature. In the United States, RDS affects 20% of infants born at a low birth weight and 30% of infants born at a very-low birth weight. Babies born by cesarean section are also at a greater risk of developing RDS. RDS occurs when baby’s lungs are underdeveloped and cannot produce surfactant which is necessary to keep the lungs open. The lack of surfactant and the underdevelopment of the lungs makes it difficult for the newborn to get oxygen to their body and to get rid of carbon dioxide. This dysfunction can result in death for the newborn if left untreated. The current treatment for RDS is artificial surfactant to keep the lungs open and sometimes mechanical ventilation to help the baby breath. There is some evidence that supplying corticosteroids to a mother at risk of premature birth or who is planning to under a cesarean delivery may reduce the risk of RDS, however to this point the results have been inconsistent and each study has had its pitfalls. Recently, a team of researchers performed a meta-analysis asking the question “Do steroids given before pregnancy prevent RDS in premature infants or baby’s born of cesarean section?”.
A meta-analysis essentially allows researchers to combine all the current literature on a topic into a powerful statistical model in order to come to a conclusion that considers all scientific information out there. In this meta-analysis, the researchers found 6 clinical trials that includes 5698 pregnancies, 3200 at risk of preterm birth and 2498 undergoing a planned cesarean delivery. They found that if a single dose of corticosteroids was given to mothers at risk of giving birth prematurely, the infants had a reduced risk of developing severe RDS and needed artificial surfactant less often compared to those whose mothers did not receive a single dose of steroids. For infants born by cesarean delivery whose mothers received a dose of steroids 48 hours before delivery , they were less likely to develop RDS (of any severity), require less mechanical ventilation, need less time on oxygen, and spend less time in the neonatal intensive care unit compared to those mothers who did not receive steroids 48 hours before delivery.
This meta-analysis provides powerful evidence that in the fight against RDS, a dose of steroids may greatly limit the burden of the disease. The study authors recommend a single dose of corticosteroids before delivery either prematurely or by cesarean section. There are limitations to the study, mostly due to the pitfalls of the studies that they are combining. The biggest one is the lack of a placebo control in some of the studies. Still, with the strength of the evidence and the number of studies combined here the results are likely to hold under more scrutiny and hopefully this can change the way we treat and prevent RDS.
Image Credit: Flickr Joshua Smith