Tanner Stages — Sexual Maturity Rating

Tanner Stages (Sexual Maturity Rating, or SMR) provide a standardised five-stage framework for assessing pubertal development, originally described by James Tanner in 1969. Assessment covers four domains: female breast development, female pubic hair, male genital development, and male pubic hair — each rated from Stage 1 (pre-pubertal) to Stage 5 (adult). A Stage 6 variant for pubic hair spread is recognised in some classification systems. This tool displays the reference tables for clinical use in paediatric and adolescent physical assessment. Tanner staging is a clinical observation framework — not a scoring instrument — and must only be assigned following direct physical examination with appropriate consent and chaperoning.

Tanner Stages — Sexual Maturity Rating (SMR)

Tanner Stages (Sexual Maturity Rating) describe the sequential pattern of pubertal development in females and males across five primary stages (with a sixth stage for pubic hair distribution in some individuals). Originally described by James Tanner in 1969, SMR provides a standardised framework for assessing pubertal progress independent of chronological age. It is used in paediatric and adolescent physical assessment to identify precocious or delayed puberty, guide anticipatory guidance, and contextualise growth and development findings. Tanner staging is a clinical observation framework, not a scoring instrument.

Clinical and Ethical Guidance

Physical examination for Tanner staging must be performed by a trained clinician with appropriate consent, chaperoning, privacy, and culturally sensitive explanation. Age norms provided are population-based estimates and vary significantly by individual, ethnicity, nutrition, and body composition. Average age of onset is earlier in Black and Hispanic females. Do not assign a Tanner stage without direct examination findings.

Female Breast Development (Tanner Stages)

Stage	Label	Clinical Description	Typical Age Range
1	Pre-pubertal	Elevation of papilla only. No glandular breast tissue. Areola not yet differentiated from surrounding skin.	Mean age ~8–11 years (pre-pubescent)
2	Breast bud	Small raised area (breast bud). Elevation of breast and papilla. Slight increase in areolar diameter. First palpable glandular tissue beneath the nipple.	Mean onset ~8.9–10.4 years
3	Further enlargement	Further enlargement and elevation of breast and areola with no separation of their contours. Glandular tissue palpable beyond areolar margin.	Mean ~11–12 years
4	Secondary mound	Projection of areola and papilla to form a secondary mound above the level of the breast.	Mean ~12–13 years
5	Mature	Mature adult-contour breast; only the papilla projects. Areola recedes to the general contour of the breast. Stage 4 morphology persists in some adult women.	Mean ~12.5–18 years

Female Pubic Hair Development (Tanner Stages)

Stage	Label	Clinical Description	Typical Age Range
1	Pre-pubertal	No pubic hair. Fine vellus hair as elsewhere on the body.	Pre-pubertal
2	Sparse, straight	Sparse growth of long, slightly pigmented, downy hair, straight or slightly curled, along the labia.	Mean ~10.5 years
3	Darker and curlier	Considerably darker, coarser, and more curled. Sparse over junction of pubes.	Mean ~11–12 years
4	Adult type, smaller area	Adult-type hair, but covering a smaller area than in the adult. No spread to medial surface of thighs.	Mean ~12 years
5	Adult	Adult quantity and type, with horizontal ('feminine') distribution. Spread to medial surface of thighs. Pubic hair may be above the mons; further spread is a Stage 6 variant.	Mean ~13 years
6	Spread up linea alba	Spread up the linea alba toward the umbilicus. Present in a minority of adults; represents late-stage development beyond Stage 5.	Variable in adults

Male Genital Development (Tanner Stages)

Stage	Label	Clinical Description	Typical Age Range
1	Pre-pubertal	Testes, scrotum, and penis are about the same size and proportion as in early childhood.	Pre-pubertal
2	Testicular enlargement	Enlargement of scrotum and testes. Skin of scrotum reddens and changes in texture. Little or no enlargement of the penis at this stage.	Mean ~9.5–11 years
3	Penile lengthening	Enlargement of the penis, which occurs at first mainly in length. Further growth of testes and scrotum.	Mean ~11–12 years
4	Penile breadth increases	Increased size of penis with growth in breadth and development of glans. Testes and scrotum larger; scrotal skin darkens.	Mean ~12–13 years
5	Adult genitalia	Genitalia adult in size and shape.	Mean ~14–17 years

Male Pubic Hair Development (Tanner Stages)

Stage	Label	Clinical Description	Typical Age Range
1	Pre-pubertal	No pubic hair. Fine vellus hair as on the abdomen.	Pre-pubertal
2	Sparse, straight	Sparse growth of long, slightly pigmented, downy hair, straight or slightly curled, at the base of the penis.	Mean ~10–11 years
3	Darker and curlier	Considerably darker, coarser, and more curled. Spread sparsely over junction of pubes.	Mean ~11–12 years
4	Adult type, smaller area	Adult-type hair, but covering a smaller area than in the adult. No spread to the medial surface of the thighs.	Mean ~12–13 years
5	Adult	Adult quantity and type, with horizontal distribution, spread to medial surface of thighs. Spread up the linea alba occurs in most males (Stage 6 variant).	Mean ~14 years
6	Spread up linea alba	Spread up the linea alba toward the umbilicus. Present in most adult males.	Variable; common in adult males

Key Clinical Applications

Precocious puberty: breast development or pubic hair before age 8 in females; testicular enlargement before age 9 in males.
Delayed puberty: no breast development by age 13 in females; no testicular enlargement by age 14 in males.
Anticipatory guidance: Tanner stage guides counselling about expected developmental changes.
Growth chart context: peak height velocity typically occurs at Stage 2–3 in females and Stage 3–4 in males.
Menarche: typically occurs at Tanner Stage 3–4 (mean age approximately 12.4 years in the U.S.).
Physiological gynaecomastia: bilateral breast tissue in males at Stages 2–3 is common and usually resolves by Stage 5.