Ananth CV, et al. - In this population-based cross-sectional analysis, researchers estimated shifts in the prevalence of chronic hypertension among pregnant women and assessed the extent to which alterations in obesity and smoking were related to these trends. They analyzed over 151 million women with delivery-associated hospitalizations in the United States during a time frame of 1970 to 2010. The overall prevalence of chronic hypertension was estimated to be 0.63% and more than a 2-fold higher rate was observed in black women vs white women. A sharp rise in the rate of chronic hypertension was noted with advancing age and period from 0.11% in 1970 to 1.52% in 2010. On average, a rise by 6% per year was noted in the rate of hypertension, with white vs black women exhibiting a slightly higher increase. Findings revealed no link of adjustments for shifts in rates of obesity and smoking, with age and period effects. Overall, chronic hypertension rates have increased substantially by age and period, from 1970 to 2010, and have displayed an over 2-fold race disparity.