On the Relationships between Sexual Maturation and Growth of Physique of Women

Abstract

This study intended to investigate the growth process in the pre- and post menarche term of Japanese women. Two-hundred and thirty-five college freshman girls who had already experienced their menarche were sampled. The subjects were classified into the following five groups: G0; which had their menarche when 10 years of age, G1; when 11 years old, G2; 12 years old, G3; 13 years old, and G4; 14 years old. The stature and body weight at the time when they had menarche were estimated from the data of stature and body weight measured in April by proportional interpolation. It was found that there were no significant differences in the growth pattern of stature and body weight between G0 and G1. At the age of menarche, the stature had reached to 93% of 18 year's height when it seemed to stop growing, but the body weight was 74% of the 18 year's weight. For stature growth, the significant difference between the two groups seemed to disappear after the age of 14 or 15 years and for the weight growth, it disappeared after the age of 17 to 18 years. It was infered that the peak velocity of stature growth appeared at 2 or 3 years before menarche and that of body weight growth at 0 to 2 years before. Soon after the menarche appeared, the growth velocity decreased considerably and the decreasing gradient was larger in the stature than in the body weight, and so was in early matured groups than in the late matured grbups. The Rohrer index decreased untill 11 years of age, and after this it tended to increase, and at 16 years of age it reached the steady state. In all the groups devided by maturation level, it was found that the changing points of tangent of straight lines fitted to the allometry points did not appear at the time when the peak velocity came, but they appeared after the growth velocity began to decrease.