Objective To investigate the influences of different factors on postpartum pelvic floor muscle injury, and provide clinical evidence to the early prevention of pelvic floor dysfunction (PFD). Methods A total of 65 630 women, who participated the postpartum pelvic floor function screening in Tianjin, from December 2011 to December 2014 were selected in this study. The uniform detect methods was used in this study. The analysis based on the PFD was diagnosed by physi?cians of Women’s and Children’s Health Center in each district. The influences of different factors on postpartum pelvic floor muscle were analyzed. Results There were 19 452 (29.6%) women suffering from postpartum pelvic floor muscle inju?ry, with the abnormal rate 29.6%, which was higher in rural areas than that in urban areas (33.9%vs 27.8%). The abnormal rate was higher in women with junior middle education or below (34.1%) than that in women with senior middle or polytech?nic schooling (30.4%), and women with college or higher education (27.7%). There was a higher abnormal rate in women with vaginal surgery delivery (40.8%) than that in women with natural delivery (32.5%) and women with caesarean section (27.2%). The muscle abnormal rate was higher in women having given two or more than two times of deliveries (34.6% , 31.5%) than those having initial delivery (29.1%). Multiple factor analyses showed that city residency, higher education and less delivery times were protecting factors for postpartum pelvic floor muscle while vaginal surgery was a risk factor for post?partum pelvic floor muscle. Conclusion There is a high incidence of postpartum pelvic floor muscle injury in the region of Tianjin. Analyzing the risk factors and strengthening the management of pelvic floor muscle injury by early prevention or ear?ly treatment would help to reduce the incidence of PFD effectively during pre-pregnancy and perinatal periods.

Objective:To explore the evolution of imaging findings on dynamic chest high resolution CT（HRCT） in patients with mild COVID-19.Methods:The data of epidemiology, clinical data and continuous dynamic chest high-resolution CT images of the patients with mild COVID-19 were analyzed retrospectively. Twenty-five patients (including 24 common type and 1 mild) were enrolled in the group, including 14 males and 11 females, with age of （42±12） years and hospital stay of （19±5） days. The basic images and dynamic images of HRCT were analyzed and compared by the radiologists.Results:The clinical manifestations were fever (22 cases), cough (18 cases), expectoration (8 cases), pharyngeal pain (6 cases). Most laboratory tests lacked specificity. There were no significant abnormalities on chest CT of one mild patient. HRCT findings of the common type were as follows: (1) the distribution of the lesions: most of the multiple lesions involved both lungs (19 cases), with average of 3 (3±1) lobes, located in the peripheral pulmonary zone near the pleura (22 cases); (2) the morphology and density of the lesions: most of the lesions were ground glass density foci (22 cases), which were patchy and massive (18 cases), nodular (10 cases) and arc broadband (7 cases); with the development of the disease, the density of some lesions increased with localized pulmonary consolidation (10 cases), accompanied by air bronchus sign (5 cases) and halo sign (5 cases). Dynamic changes of HRCT images in the chest: the positive manifestations were found on the 5th (5, 6) day after the onset of the disease, the progressive time of CT lesions was 5 (5, 7) days, the peak time of CT lesions was 11 (10, 13) days, and the turning time of CT lesions was 9 (8, 11) days.Conclusions:Dynamic chest HRCT can monitor the basic evolution process of the disease in patients with mild COVID-19, and provide a more intuitive basis for clinical early diagnosis and treatment.