A single‐center retrospective study of the clinical significance of chorionic bump at early stage of gestation

The chorionic bump is a distinct rare sonographic abnormality. Until now, there is contradictory evidence about if it associates with poor pregnancy outcomes. We performed this retrospective study to provide additional clinical data to investigate the clinical significance of chorionic bump at early stage of pregnancy.A single-center retrospective study was performed using the sonographic and clinical data of the pregnant women who had antenatal checkup and childbirth at Shanghai First Maternal and Child Health Care Center from December 2018 to December 2019. Sonographic examination was performed by experts at 5-10 weeks' gestation. Maternal age and gestational age matched controls from the same period were selected for analysis.We observed 83 chorionic bump cases showing a prevalence of 0.33%. We found previous intrauterine operations and/or adverse maternal history posed a risk of having chorionic bump. In our cohort, chorionic bump associates with poor pregnancy outcomes. Poor pregnancy outcomes were more frequently found in the patients whose lesions were detected early (<56 days of pregnancy), or in the patients with the lesion relative sizes more than 40% of the sizes of the gestational sac, or in the patients with multiple lesions.Intrauterine operations and/or adverse maternal history associate with an increased incidence of chorionic bump, which associates with poor pregnancy outcomes. Early detection, bigger relative size, and multiple lesions are factors likely leading to poor pregnancy outcomes.