Before revision: In the United States, an analysis of 10,590 women aged 15–44 taken from the 2013–2017 round of the CDC ’ s National Survey of Family Growth found a median age of 11.9 years (down from 12.1 in 1995), with a mean of 12.5 years (down from URL Physiology Puberty Menarche is the culmination of a series of physiological and anatomic processes of puberty: Attainment of a sufficient body mass (typically 17% body fat).
After revision: In the United States, an analysis of 10,590 women aged 15–44 taken from the 2013–2017 round of the CDC ' s National Survey of Family Growth found a median age of 11.9 years (down from 12.1 in 1995), with a mean of 12.5 years (down from URL Physiology Puberty Menarche is the culmination of a series of physiological and anatomic processes of puberty: Attainment of a sufficient body mass (typically 17% body fat).