Effect of single and multiple courses of maternal betamethasone on prenatal congenital lung lesion growth and fetal survival

PurposeAdministration of maternal betamethasone (BMZ) is a therapeutic option for fetuses with large microcystic congenital lung lesions at risk for, or causing, hydrops. Not all fetuses respond to a single course of BMZ. We review our experience with the use of single and multiple courses of maternal BMZ for the management of these patients.MethodsA retrospective review of fetuses with congenital lung lesions managed with maternal BMZ from 2003 to 2014 was performed.ResultsForty-three patients were managed with prenatal steroids (28 single course, 15 multiple courses). Single course recipients demonstrated a reduction in lesion size and resolution of hydrops in 82% and 88% of patients respectively compared to 47% and 56% in recipients of multiple steroid courses. Survival of multiple course patients (86%) was comparable to that of single course patients (93%) and improved compared to non-treated historical controls. Multiple course recipients demonstrated an increased need for open fetal surgery and postnatal surgery at a younger age.ConclusionFetuses who fail to respond to a single course of BMZ may benefit, as indicated by hydrops resolution and improved survival, from additional courses. However, failure to respond is indicative of a lesion which may require fetal or immediate neonatal resection.