Few studies have characterized life course hair product usage beyond ever/never. We investigated hair product use from childhood to adulthood, usage patterns in adulthood, and socioeconomic status (SES) correlates among African-American (AA) women. Using self-reported data from 1,555 AA women enrolled in the Study of Environment, Lifestyle, and Fibroids (2010-2018), we estimated the usage frequency of chemical relaxer/straightener (≥twice/year, once/year, rarely/ never) and leave-in/leave-on conditioner (≥once/week, 1-3 times/month, rarely/never) during Users may view, print, copy, and download text and data-mine the content in such documents, for the purposes of academic research, subject always to the full Conditions of use: