Objective To explore the incidence of pregnancy-related VTE in China and to assess the associations of maternal weight gain in different periods of pregnancy with VTE. Design Retrospective case-control study. Setting Shanghai, China Participants 151 cases (11.7 per 10000) of pregnancy-related venous thromboembolism (VTE) and 302 controls. Methods GWG was standardized into gestational age-specific z-scores stratified by body mass index (BMI) and categorized as low (< -1), normal (-1 to 1), and high (>1). The adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were estimated through log-binomial regression models. Main outcome measures Pregnancy-related VTE Results There were 65.6% of pulmonary embolus (PE) and 34.4% of deep venous thrombosis (DVT) alone or combined with PE. Among normal-weight women, there was observed protective effects of low weight gain (aOR 0.79; 95% CI 0.37–1.68) and significantly increased risks of high weight gain (aOR=1.47; 95% CI: 1.03-2.09) for PE in early pregnancy. Similarly, a tendency towards decreased risk at lower weight gain throughout pregnancy (aOR 0.79; 95% CI 0.37–1.68) and significantly increased risk at higher values (aOR=1.52; 95% CI: 1.01-2.31) for PE was observed. As for underweight and overweight women, results from the categorical model for early, late or total pregnancy weight gain indicated an increased risk in PE at both low and high weight gain, but confidence intervals were wide. Conclusion Maternal weight gain in total or early pregnancy is an important risk factor for PE. Intensive weight management that continues through pregnancy may be indispensable to effectively improve pregnant outcomes.

Objective To assess the incidence of uterine rupture, its association with previous uterine surgery and vaginal birth after a caesarean section (VBAC), and the maternal and perinatal implications. Design Population-based retrospective study. Setting Shanghai, China. Participants A total of 209,112 deliveries were attended and 41 uterine rupture cases were included. Methods All pregnant women treated for ruptured uterus in one center between 2013 and 2020 were included. Their case folders retrieved from the medical records room were retrospectively reviewed. Main outcome measure Adverse maternal and neonatal outcomes. Results The incidence of uterine rupture was 1.96/10 000 births. 16 (39.0%) had maternal and fetal complications. There were no maternal deaths secondary to uterine rupture, while perinatal mortality attributable to uterine rupture was 7.32 %. Among all case, 38 (92.68%) were scarred uterus and 3(7.32%) were unscarred uterus. The most common cause of uterine rupture was previous cesarean section while cases with a history of laparoscopic myomectomy often had serious adverse outcome. 24 (59%) of ruptures were anterior lower uterine segment. Fetal heart rate monitoring changes are the most reliable presenting clinical symptom in our study. Conclusion Incidence of uterine rupture in the study area was consistent with developed countries. Further improvement in obstetric care and strong collaboration with referring health facilities was needed to ensure maternal and perinatal safety.