To assess the value of prenatal ultrasound and genetic evaluation in the clinical prenatal diagnosis and management of fetal gastrointestinal obstruction.

A total of 82 pregnant women with fetal gastrointestinal obstruction detected by prenatal ultrasound and evaluated via multidisciplinary consultation from August 2022 to August 2025, at Women's Hospital of Nanjing Medical University were enrolled, including 44 cases of upper gastrointestinal obstruction and 38 cases of lower gastrointestinal obstruction. Prenatal ultrasound characteristics, genetic testing results, and perinatal outcomes were systematically analyzed and compared between the two groups.

Among the 44 cases of upper gastrointestinal obstruction, 28 (63.6%) presented with isolated obstruction, while 16 (36.4%) were complicated with other structural malformations. According to ultrasound classification, there were 32 cases (72.7%) of duodenal obstruction (double-bubble sign), 11 cases of esophageal atresia, and 1 case of pyloric obstruction. Chromosomal microarray analysis (CMA) was performed in 32 cases, revealing a significantly higher abnormality detection rate in the complicated malformation group (5/10, 50.0%) than in the isolated group (2/22, 9.1%; P＜0.05). The prenatal termination rate was 34.1% (15/44). Among the 25 cases of isolated obstruction that continued pregnancy, the neonatal survival rate was 88.0% (22/25), with all 3 neonatal deaths occurring in cases of esophageal atresia. In the complicated malformation group, 1 case resulted in intrauterine fetal death, while the remaining 3 neonates survived. Regarding the 38 cases of lower gastrointestinal obstruction, 28 (73.7%) were isolated and 10 (26.3%) were complicated with other structural malformations, with characteristic intestinal dilatation observed on ultrasound in all cases. CMA was performed in 30 cases, showing a higher abnormality detection rate in the complicated malformation group (3/9, 33.3%) than in the isolated obstruction group (1/21, 4.8%), although this difference did not reach statistical significance (P=0.128). The prenatal termination rate of pregnancy was 13.2% (5/38). The neonatal survival rate was 100% for both isolated obstruction and complicated malformation cases.

Fetal gastrointestinal obstruction exhibits characteristic features on prenatal ultrasound. The risk of chromosomal abnormalities increases significantly when obstruction is accompanied by other structural anomalies. Isolated lower gastrointestinal obstruction carries the best prognosis, while esophageal atresia among upper gastrointestinal obstructions is assocated with a poorer prognosis.