BackgroundThis research aims to summarize the ultrasound features and pregnancy outcomes of incarceration of the gravid uterus (IGU), providing a basis for clinical management.MethodsA retrospective cohort study was conducted on pregnant patients with IGU at Hunan Provincial Maternal and Child Health Care Hospital in China, spanning from September 30, 2016, to May 31, 2024. Data on maternal age, parity, medical history, risk factors, gestational age, clinical manifestations, ultrasound examination, treatment methods, time, and method for terminating pregnancy, and pregnancy outcomes were collected. We compared cases diagnosed before and after 20 gestational weeks.ResultsDuring the study period, 13 pregnant women were diagnosed with IGU, and 140 162 deliveries were recorded at our hospital. Two cases were referred from other hospitals and did not deliver in our hospital. Accordingly, the incidence of IGU was 0.08‰ (11/140, 162). The most prevalent risk factor for IGU was previous abdominal or pelvic surgery (61.54%, 8/13). Dysuria or even urinary retention was the primary symptom (38.46%, 5/13). Spontaneous resolution occurred in only one case (7.69%). All cases were detected using prenatal ultrasound examination with typical characteristics, including a retroverted uterus and the fundus located behind the cervix. No statistically significant differences between the two comparison groups were found in successful uterine reduction (p > 0.05).ConclusionThe definition of IGU should include symptomatic cases of any gestational age. Despite a low prevalence of this pregnancy complication, the overall prognosis of IGU is good. In the absence of severe symptoms, regular monitoring may be an option. Typical ultrasound imaging features enable a definitive diagnosis of IGU.