Effect of single and multiple courses of maternal betamethasone on prenatal congenital lung lesion growth and fetal survival.
Administration 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. A retrospective review of fetuses with congenital lung lesions managed with maternal BMZ from 2003 to 2014 was performed. Forty-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. Fetuses 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.