Menarche
Menarche is a girl's first menstrual period. In well-fed populations the median age has stayed between 12 and 13 years, and 98 percent of girls have reached it by age 15.1
Early cycles are often long and uneven. After menarche, 90 percent of cycles run 21 to 45 days, and by the third year most run 21 to 34 days.1 A regular bleed is not proof of ovulation.
The cycle serves as a vital sign from the start. A gap of 90 days, no period by age 15, or no period within three years of breast budding each call for a search for the cause.2 Charting early builds body literacy a girl keeps for life.
Cited in this entry
- ACOG. ACOG Committee Opinion No. 651: Menstruation in Girls and Adolescents: Using the Menstrual Cycle as a Vital Sign. Obstetrics and Gynecology. 2015. https://pubmed.ncbi.nlm.nih.gov/26595586/
- American Academy of Pediatrics Committee on Adolescence, American College of Obstetricians and Gynecologists Committee on Adolescent Health Care, Diaz A, Laufer MR, Breech LL. Menstruation in girls and adolescents: using the menstrual cycle as a vital sign. Pediatrics. 2006. https://pubmed.ncbi.nlm.nih.gov/17079600/
This content is for educational purposes only and does not constitute medical advice. Consult an RRM clinician or healthcare provider for guidance specific to your situation.
