KNOWN RISK FACTORS MAY ACCOUNT FOR ONLY PART OF THE U.S. INCREASE IN LIFE-THREATENING CHILDBIRTH COMPLICATIONS: In the U.S., severe maternal morbidity has more than doubled over the last 15 years. At the same time, pre-pregnancy maternal health factors like maternal age, obesity, and comorbidities have also increased, and so too have rates of cesarean deliveries. Could these upward trends be related? Surprising research findings show that pre-pregnancy maternal health factors and rates of cesarean deliveries do not explain the uptick in severe maternal morbidity in California from 2007 to 2014. During that time period, severe maternal morbidity increased by 65 percent and affected nearly 48,000 women who delivered in the state. Investigators found severe maternal morbidity was associated with advanced maternal age, pre-pregnancy comorbidity, and cesarean delivery, but not pre-pregnancy obesity. However, changes in these risk factors did not account for the increase in severe maternal morbidity over time. The open access study was published in BMC Pregnancy and Childbirth, with lead author and postdoctoral scholar Stephanie Leonard, PhD, senior author Suzan Carmichael, PhD, and co-author Elliott Main, MD.