·A total of 283 maternal near miss admitted to ICU of Southern District of Shanghai General Hospital, Shanghai Jiao Tong University from January 2007 to December 2018 were selected. According to whether the main cause of ICU admission was related to pregnancy, the patients were divided into pregnancy complication group (175 cases) and pregnancy comorbidity group (108 cases). Statistical methods were used to compare the differences of the clinical data between the two groups.

·The top three diseases in the pregnancy complication group were hypertensive disorders complicating pregnancy, obstetric hemorrhage and metabolic disorders caused by hyperemesis gravidarum. The top three diseases in the pregnancy comorbidity group were pregnancy with heart disease, infection and acute pancreatitis. Compared with the pregnancy comorbidity group, the average age of pregnant and postpartum women in the pregnancy complication group was older, the number of multipara and irregular birth examination were more, Acute Physiology and Chronic Health Evaluation Ⅱ (APACHE Ⅱ) was higher, and the number of medical puncture procedure (thoracentesis, abdominocentesis, lumbar puncture and bone marrow puncture) was less (all P<0.05).

·There are many causes of ICU admission for maternal near miss. In-depth analysis of the clinical characteristics of this kind of pregnant women will help ICU physicians better understand and manage acute critical illness in obstetrics.