Brémont was born as Marie Marthe Augustine Mesange in Noëllet, and her first husband, railroad worker Constant Lemaitre, was killed in the First World War. She married again to a taxi driver, Florentin Brémont, who died in 1967.
Over the course of her life, she worked in a pharmaceutical factory, as a nanny and as a seamstress. At 103, she was hit by a car and broke her arm. She died at her retirement home at age 115 years 42 days in Candé, Maine-et-Loire, having had no children, and was the last documented surviving person born in 1886.