Maternal early pregnancy blood pressure and risks for preeclampsia
Table 2 presents crude ORs and adjusted ORs for this association. While it turned out that 241 women with elevated blood pressure developed preeclampsia (2.03%; OR 1.57; 95% CI: 1.35 to 1.83), 845 women with stage 1 hypertension developed preeclampsia (4.57%; OR 3.24; 95% CI: 3.26 to 4.06) and 577 women with stage 2 hypertension developed preeclampsia (9.45%; OR 7.92; 95% CI: 7.02 to 8.94) compared with 541 women with normal blood pressure who developed preeclampsia (1.30%) (Table 2 ).
After adjusting for maternal age, years of education, parity and birthplace, the adjusted odds ratios (AORs) (95% CI) were 1.45 (1.24 to 1.69) for elevated blood pressure women, 3.16 (2.83 to 3.53) for stage 1 hypertension women and 6.15 (5.42 to 6.98) for stage 2 hypertension women (Table 2 ).