IL6 and major depressive disorder: For example, outside of pregnancy, commonly studied inflammatory markers, such as interleukin-1, interleukin-6, and C-reactive protein, have been shown to be positively associated with depression.62 In pregnancy specifically, individuals with a history of depression have increased plasma C-reactive protein and glycoprotein acetyls.63 Similarly, increased levels of these markers have been shown to be associated with PE.64,65