Impact of high‐risk prenatal screening results for 22q11.2 deletion syndrome on obstetric and neonatal management: Secondary analysis from the SMART study

Abstract

ObjectiveOne goal of prenatal genetic screening is to optimize perinatal care and improve infant outcomes. We sought to determine whether high‐risk cfDNA screening for 22q11.2 deletion syndrome (22q11.2DS) affected prenatal or neonatal management.MethodsThis was a secondary analysis from the SMART study. Patients with high‐risk cfDNA results for 22q11.2DS were compared with the low‐risk cohort for pregnancy characteristics and obstetrical management. To assess differences in neonatal care, we compared high‐risk neonates without prenatal genetic confirmation with a 1:1 matched low‐risk cohort.ResultsOf 18,020 eligible participants enrolled between 2015 and 2019, 38 (0.21%) were high‐risk and 17,982 (99.79%) were low‐risk for 22q11.2DS by cfDNA screening. High‐risk participants had more prenatal diagnostic testing (55.3%; 21/38 vs. 2.0%; 352/17,982, p < 0.001) and fetal echocardiography (76.9%; 10/13 vs. 19.6%; 10/51, p < 0.001). High‐risk newborns without prenatal diagnostic testing had higher rates of neonatal genetic testing (46.2%; 6/13 vs. 0%; 0/51, P < 0.001), echocardiography (30.8%; 4/13 vs. 4.0%; 2/50, p = 0.013), evaluation of calcium levels (46.2%; 6/13 vs. 4.1%; 2/49, P < 0.001) and lymphocyte count (53.8%; 7/13 vs. 15.7%; 8/51, p = 0.008).ConclusionsHigh‐risk screening results for 22q11.2DS were associated with higher rates of prenatal and neonatal diagnostic genetic testing and other 22q11.2DS‐specific evaluations. However, these interventions were not universally performed, and >50% of high‐risk infants were discharged without genetic testing, representing possible missed opportunities to improve outcomes for affected individuals.