Objective:To explore the diagnostic value of first-trimester and mid-trimester ultrasound in screening fetal pentalogy of Cantrell, and to analyze missed and misdiagnosed cases.Methods:The fetal ultrasound image characteristics of pentalogy of Cantrell diagnosed in the Affiliated Suzhou Hospital of Nanjing Medical University from March 2018 to November 2022 were retrospectively analyzed. The necessary sections and key features of ultrasound images for diagnosing the disease in first-trimester and mid-trimester were summarized. The diagnostic value of ultrasound screenings in first-trimester and mid-trimester was analyzed, and the progression of the disease during pregnancy was understood, the missed diagnosis rate and misdiagnosis rate were calculated, and the reasons for missing diagnosis were analyzed. All fetuses were followed up to birth or induction of labor.Pentalogy of Cantrell was divided into types Ⅰ, Ⅱ, and Ⅲ according to Toyama′s research.Results:Among the 120 190 fetuses, 13 cases of pentalogy of Cantrell were diagnosed by ultrasound in first-trimester and mid-trimester. Ultrasound predominantly showed the fetal heart being malpositioned outside the chest and the fetal abdominal contents bulging outside the abdominal cavity, and the sternumal echo was partially or completely missed in some cases. All 13 cases were confirmed by follow-up, including 1 case of type Ⅱ, and 12 cases of type Ⅲ. In addition, 1 missed case of type Ⅱ pentalogy of Cantrell was followed up after birth. The correct diagnostic rates of fetal pentalogy of Cantrell using standard ultrasound sections during the first-trimester and mid-trimester were 99.9% and 100%, the sensitivity were 88.9% and 100%, the specificity were both 100%, the positive predictive values were both 100%, and the negative predictive values were 99.9% and 100%, respectively.Conclusions:First-trimester and mid-trimester ultrasound screenings have high diagnostic accuracy for pentalogy of Cantrell, and early detection and early diagnosis are of great clinical significance for the guidance of pregnancy outcomes.