Definition and epidemiology
Delayed puberty in a girl is defined as absence of breast development (thelarche) by age 13 years, or failure to reach menarche by age 15 (or within ~3 years of thelarche). These are statistical thresholds (~2–2.5 SD from the mean). Unlike in boys, constitutional delay is a less dominant cause in girls, so a girl meeting the threshold has a comparatively higher prior probability of underlying pathology and deserves a low threshold to investigate. The two broad mechanisms are hypergonadotropic hypogonadism (primary ovarian failure — most importantly Turner syndrome, which accounts for a substantial share of primary amenorrhoea) and hypogonadotropic hypogonadism (central — functional from undernutrition/eating disorders/excessive exercise/chronic illness, or organic from CNS lesions, congenital GnRH deficiency or hyperprolactinaemia).
Clinical features
Distinguish absent thelarche (gonadal/central axis problem) from normal breast development with primary amenorrhoea (which raises an anatomical/outflow cause such as Müllerian agenesis or androgen insensitivity). Look for the Turner phenotype: short stature, webbed neck, widely spaced nipples, cubitus valgus, lymphoedema, cardiac (coarctation, bicuspid valve) and renal anomalies. Low body weight, intense athletic training, or features of an eating disorder point to functional hypothalamic suppression. Anosmia suggests Kallmann; galactorrhoea suggests hyperprolactinaemia; virilisation suggests an androgen excess disorder.
Diagnosis
First-line tests are early-morning LH, FSH and estradiol with a bone-age radiograph; add TSH, prolactin and coeliac screen. The gonadotropin level is the key fork: elevated LH/FSH (hypergonadotropic) mandates a karyotype to identify Turner syndrome or other gonadal dysgenesis; low/normal LH/FSH points to a central cause and warrants assessment of nutrition, chronic illness and, where indicated, MRI brain/pituitary. When breast development is present but the uterus is absent or amenorrhoea is anatomical, pelvic ultrasound and karyotype/testosterone help separate Müllerian agenesis from androgen insensitivity.
See the full criteria: Delayed Puberty in Female
Red flags
- Short stature with delayed puberty and dysmorphic features — Turner syndrome (karyotype)
- Elevated gonadotropins at any age — primary ovarian failure
- Headache, visual field defect, galactorrhoea or diabetes insipidus — CNS/pituitary lesion
- Anosmia with absent puberty — congenital GnRH deficiency (Kallmann)
- Marked low weight, disordered eating or over-exercise — functional hypothalamic amenorrhoea
- Normal breasts with absent uterus or cyclical pain without menses — anatomical/outflow cause
Management overview
Treatment follows the cause. Confirmed hypogonadism (Turner syndrome, gonadal dysgenesis, organic central deficiency) needs endocrinology referral for carefully titrated, gradually escalating estrogen to induce puberty and protect bone, with later progestin and (in Turner) attention to cardiac, renal, thyroid and growth issues — exact regimens are specialist-led and out of scope here. Functional hypothalamic delay is managed by correcting the driver: restoring energy balance, treating chronic illness or an eating disorder. Suspected CNS lesions need prompt imaging and referral. In India, actively exclude coeliac disease, thalassaemia/chronic anaemia, hypothyroidism and undernutrition, and have a low threshold for karyotyping a short girl with delayed puberty, as Turner syndrome is frequently diagnosed late.
References
- Merck Manual Professional Edition — Delayed Puberty.
- Klein DA, et al. Am Fam Physician. 2019;100:39–48 (amenorrhoea).
- J Endocr Soc. 2022;6(9):bvac108 (delayed puberty with elevated gonadotropins).
Decision support for qualified clinicians only — verify against current primary guidelines and your clinical judgement.