Objective:To summarize the prenatal diagnosis and postnatal follow-up of 15q11.2 BP1-BP2 microdeletion syndrome (Burnside-Butler syndrome, BBS), and provide a reference for the management of BBS.Methods:A retrospective analysis was performed on 27 singleton pregnancies with fetal BBS that were prenatally diagnosed by single nucleotide polymorphism(SNP) array of amniotic fluid in Wuxi Maternity and Child Health Care Hospital from January 2017 to September 2021. Prenatal diagnosis indications, serological screening, prenatal ultrasound features, SNP array results, and postnatal growth and development were described and summarized.Results:(1) Of the 27 cases, the indications of prenatal diagnosis in 14 cases were abnormal sonographic findings, including eight cases with increased nuchal translucency, two with cleft lip and palate/alveolar process cleft, one with fetal multiple joint contracture syndrome, one with fetal right diaphragmatic hernia and single umbilical artery, one with suspected fetal duodenal atresia and one with nasal bone absence. Other indications included high risk of Down syndrome by serological screening in six cases, history of adverse pregnancy in six cases, and advanced age in one case. (2) Karyotyping of amniotic fluid in these 27 BBS fetuses showed normal results and SNP array indicated the deletion range of 311.8-855.3 kb. Parental verification of 23 cases confirmed one was a new mutation, seven were inherited from the father and 15 from the mother. (3) Five pregnancies were terminated in the second trimester and the remaining 22 cases were live births. (4) The median follow-up of the 22 children was 1 year 8 months (range 0.5 months to 4 years 3 months), which found low body weight and/or growth retardation in six cases, low body weight with language retardation in one case, low body weight with growth retardation and hyperactive behavior in one case, language retardation with left ear appendage in one case, cleft palate accompanied by duodenum/cleft lip and alveolar cleft in two cases without abnormal development after surgical treatment, and no abnormal growth in the remaining 11 cases.Conclusion:For BBS fetuses, the proportion of ultrasound abnormalities is high but with a low specificity in prenatal diagnosis, and the risk of abnormal postnatal growth and development/behavior is high, which requires continuous monitoring.