The growth in height, upper segment and biiliac diameter after the menarche has been studied in 40 girls followed longitudinally until the mean age of 18 years 3 months. The mean increase in height after the menarch was 7.3 +/- 2 cm., with significant individual variations. The upper segment was responsible for much of the total increase, which was greater with an early menarche. The percentage of the final height attained by the menarche was constant: 95.5 % +/- 1,2 %. After cessation in height growth, the biiliac diameter still increased for 75 % of the children. The median value for this increase after the menarche was 2 cm., with a significant scatter. The increase in these three parameters was in indirect correlation with the bone age: the less the bone age at the menarche, the greater the increase in height, upper segment and biiliac diameter.