IntroductionThe purpose of the present study is to evaluate our institutional management of high-risk congenital lung malformations (CLM) with particular consideration of the use of multiple maternal steroid courses and maternal steroids in CLMs with pathologies other than congenital pulmonary airway malformation (CPAM). MethodsA single-center retrospective review was performed for all fetuses evaluated for CLM who received maternal steroids and/or had a CLM volume ratio (CVR) ≥ 1.6 (2015-2020). Fetuses were categorized as receiving no steroids, single steroid, or multiple steroid courses. Outcomes evaluated included CVR growth rate, resolution of early hydrops, and resolution of hydrops. Results are reported with a descriptive analysis. ResultsNineteen patients were identified who had CVR ≥ 1.6 (single steroid course 9/19, multiple steroid courses 6/19, and no steroids 4/19). A majority (n = 13, 68%) of all lesions had a reduction or no change in CVR between initial and final measurements (single steroid course 7/9, 78%; multiple steroid courses 4/6, 67%). When evaluating by pathology, ≥ 50% of each classification had reduction or no growth of CVR (CPAM 7/11, bronchial atresia 2/4, sequestration 3/3, congenital lobar emphysema 1/1). Seventy five percent (3/4) of lesions with early hydrops had resolution following steroid treatment (single steroid course 1, multiple steroid courses 2). Of the four lesions that had hydrops, only one had resolution after receiving multiple steroid courses. ConclusionsOur institutional experience reports the majority of CLM (including pathologies other than CPAM) who received steroids had reduction or no change in CVR. Given the low risk-benefit ratio of maternal steroids, physicians could consider use of multiple steroid courses for CLM refractory to a single course.