Abstract:Objective To observe the incidence of adverse pregnancy outcome in pregnant women with clockwise cardiac rotation indicated by electrocardiogram(ECG) and analyze its clinical significance. Methods A retrospective study was performed on 12 827 pregnant women who were admitted to Guangdong Province Maternity and Child Health Hospital for ECG examination from January 1st, 2016 to December 31st, 2018(from card establishment to 27⁺6 weeks of gestation). The participants were dichotomized two groups according to the presence and absence of clockwise rotation in ECG. The associations of clockwise rotation with stillbirth, preeclampsia and thrombotic disease were analyzed. The significant covariates(including age, body mass index, gravidity, parity, gestational hypertension, multiple pregnancy, gestational diabetes mellitus and pregestational diabetes mellitus) using univariate analysis were adjusted by multivariate logistic analysis. Results Out of the pregnant women in middle and early pregnancy, there were 134 pregnant women with clockwise cardiac rotation and 12 693 pregnant women without cardiac transposition. The incidence of thrombotic disease in patients with clockwise rotation was significantly higher than that in patients without clockwise rotation ［2.24%(3/134) vs 0.07%(9/12 693), P＜0.01］. After multivariable adjustment, the risk of thrombotic disease in pregnant women with clockwise rotation remained significantly higher(OR=28.824, 95%CI: 7.248-114.618, P＜0.01). Conclusion Although the prevalence of ECG-indicated clockwise rotation is low among pregnant women during pregnancy, it may be related to thrombotic disease, suggesting that further screening should be conducted for the related risks of thrombotic disease.