Makindo Medical Notes

Improved nutritional status and increased obesity in particular are driving earlier onset of puberty

About

• Delayed puberty : age onset > 2.5 SD above the national average
• In the UK 13 years in girls and 14 years in boys.

Aetiology

• Puberty initiated by pulsatile increases in GNRH by the hypothalamus
• This stimulates pulsatile release of luteinising hormone (LH) and follicle-stimulating hormone (FSH) by the pituitary.
• Chronic ill health causes functional hypogonadotrophic hypogonadism.
• Steroids/Glucocorticoid

Investigations

• X-ray of the left wrist can assess bone age accurately. Bone age> 2 years behind the chronological age should prompt consideration of further investigations. Bone ages can be determined because of the fusion of the epiphyses as puberty progresses, increases in bone mineral content and density as the skeleton grows,
• Alkaline Phosphatase is elevated normally

Girls

• Absent breast development by 14
• Absent pubic hair at 14
• More than 5 years between start and completion of breast growth
• Menarche (periods begin) absent by age of 16

Boys

• No testicular enlargement by 14
• No pubic hair by age 15
• More than 5 years between start and completion of external genitalia

Breast development.

• Stage B1: prepubertal, elevation of the papilla only.
• Stage B2: breast buds visible or palpable with enlargement of the areola.
• Stage B3: further enlargement of the breast and areola with no separation of their contours
• Stage B4: projection of areola and papilla to form a secondary mound over the rest of the breast.
• Stage B5: mature breast with projection of papilla only.

Male genital development

• Stage G1: prepubertal.
• Stage G2: enlargement of testis to more than 2.5 cm, the appearance of scrotal reddening, and increase in rugations.
• Stage G3: increase in length and to a lesser extent breadth of penis with further growth of testis.
• Stage G4: further increase in size of penis and testes and darkening of scrotal skin.
• Stages G5 and G6: adult genitalia.

Pubic hair growth among boys

• Stage P1: preadolescent, no pubic hair.
• Stage P2: sparse growth of slightly pigmented, slightly curved pubic hair mainly at the base of the penis.
• Stage P3: thicker curlier hair spread laterally.
• Stage P4: adult-type hair that does not yet spread to medial thighs.
• Stage P5 adult-type hair spread to medial thighs.

Appearance of pubic and labial hair among girls

• Stage PH1: prepubertal, no pubic hair.
• Stage PH2: sparse growth of long, straight, or slightly curly minimally pigmented hair, mainly on labia.
• Stage PH3: considerably darker and coarser hair spreading over mons pubis.
• Stage PH4: thick adult-type hair that does not yet spread to the medial surface of the thighs.
• Stage PH5: hair is adult type; distributed in the classic

Females

• Thelarche (breast buds) 1st sign of puberty at about 11yo, followed by adrenarche (pubic hair).
• About 1yr after thelarche at Tanner 3, peak growth spurt occurs.
• About 6mo after growth spurt at Tanner 4, menarche occurs. Breast development from Tanner 2-5 takes 4yrs on avg. and pubic hair development takes 2.5yrs.

Males

• Testicular growth at about 11.5yrs is 1st puberty sign, marking Tanner 2.
• Pubic hair appears next with penile enlargement within 1yr of testicular enlargement.
• Progression to Tanner 5 over 3yrs, with growth spurt in Tanner 4-5.

Causes