To investigate the prenatal ultrasonographic features and clinical characteristics of fetuses with Pierre Robin sequence (PRS) and analyze the correlation between prenatal ultrasound findings and postnatal clinical outcomes, so as to provide reference for prenatal diagnosis and perinatal management.

A retrospective analysis was conducted on 23 fetuses diagnosed with PRS by prenatal ultrasound at Chongqing Health Center for Women and Children between January 2019 and December 2024. All cases were confirmed by postnatal examination or postmortem evaluation following termination of pregnancy. Multiphase ultrasound assessments were performed, including quantitative measurements of the inferior facial angle (IFA) and jaw index (JI), as well as morphological evaluations of glossoptosis and cleft palate types. Associated malformations were also recorded. Clinical data, genetic testing results (including chromosomal microarray analysis and whole-exome sequencing [WES]), and pregnancy outcomes were collected to systematically summarize the clinical features and prognostic factors of PRS fetuses.

Regarding ultrasonographic features, all 23 cases exhibited micrognathia (IFA range: 33.7°~49.6°, mean: 44.2°±3.8°; JI range: 21.4~46.1, mean: 31.1±6.7) and glossoptosis (100%). Cleft palate was detected in all cases (23/23), with U-shaped cleft palate accounting for 26.1% (6/23). Associated malformations were present in 52.2% (12/23) of cases, with circulatory system anomalies (26.1%, 6/23) and nervous system anomalies (21.7%, 5/23) being the most frequently observed. Genetic testing was conducted in 7 cases, of which 2 exhibited variants of uncertain significance (VUS) on WES. Regarding pregnancy outcomes, termination of pregnancy was elected in 19 cases, while the remaining 4 cases continued to term, resulting in live births (3 isolated PRS, 1 with cardiac anomaly). Among the live births, 3 required mechanical ventilation for respiratory support, while 1 did not. All 4 neonates underwent postnatal surgical intervention, and favorable outcomes were observed during the 1-year follow-up.

Prenatal diagnosis of PRS requires integrated multiphase ultrasound and genetic testing. Multidisciplinary stratified management may improve pregnancy outcomes and prognosis, particularly in isolated cases.