In 2017, the American College of Cardiology (ACC) and American Heart Association (AHA) guidelines built on evidence that elevated blood pressure increases cardiovascular mortality in the general population, Reclassification of BP; however, these diagnostic definitions do not include pregnant women, and whether newly diagnosed stage 1 hypertension affects pregnancy complications remains unclear. In this study, the combination of maternal factors, MAP and PLGF was used to comprehensively analyze the risk factors of preeclampsia through the Bayesian rule developed by the British Fetal Medicine Foundation (FMF). According to the guidelines and consensus, the pregnant women were considered to be at high risk when the calculated risk was higher than 1% of the population. To compare the pregnancy outcomes of women with normal blood pressure in the first trimester and stage 1 hypertension in different risk groups, and to find out whether screening for preeclampsia can be omitted for women with normal blood pressure in the first trimester, while screening for preeclampsia should still be performed for women with stage 1 hypertension as an independent moderate risk factor, and finally to optimize the screening strategy for preeclampsia.