VARIATIONS IN PATTERN OF PUBERTAL CHANGES IN GIRLS

Mixed longitudinal data on the physical changes at puberty in 192 normal girls are presented, together with pictorial standards for stages of breast and pubic hair development. The first sign of puberty (i.e. either breast or pubic hair development) appeared between the ages of 8.5 years and 13 years in 95% of girls, and the breasts reached the mature stage between 11.8 and 18.9 years. The mean ages at which the intermediate stages of breast and pubic hair development were reached are given; all had standard deviations of approximately 1 year. The mean age at peak height velocity (i.e. the maximum rate of growth in stature) was 12.14 ± ±0.14 (SD =0.88) and the mean age at menarche was 13.47 ± 0.10 (SD = 1.02). The limits of normal variation in the length of time which girls take to pass from one stage of breast or pubic hair development to another are given. The interval from the first sign of puberty to complete maturity varied from 1.5 years to over 6 years. The bud stage of breast development persisted for between 6 months and 2 years before further change took place. The mean interval from the beginning of breast development to menarche was 2.3 ± 0.1 years, but the range observed was 6 months to 5 years 9 months. The mean interval from the beginning of breast development to peak height velocity was 1.01 ±0.12 years (SD = 0.77). The limits of normal variation in the relation between breast and pubic hair development, the adolescent growth spurt, and menarche are described. Peak height velocity was reached very early in puberty by about 25% of girls, and in all cases it preceded menarche. 90% of girls had menstruated before their breasts reached the mature stage. Pubic hair was seen before breast development had begun in about a third of all girls. The use of these data in making a clinical distinction between normal and abnormal puberty is discussed, together with their relevance to the study of the neuro-endocrine mechanisms by which puberty is controlled.