Critical weight at menarche. Critique of a hypothesis.

The critical weight hypothesis in relation to menarche, which is known as the Frisch-Revelle model, has been examined. Since, in eight samples, girls reached menarche at weights spanning a 71.4-kg (157-lb) range, Frisch and Revelle's concept of a critical weight of 47 to 48 kg (104 to 106 lb) cannot be applied meaningfully to individuals. Neither can the suggestion of an invariant mean weight be accepted, because significant differences occur among the mean menarcheal weights for several samples of normal white girls. Finally, when stature is held constant, there is some evidence that girls who reach menarche at younger ages are heavier than those who begin menstruating at older ages. Apparent reductions in variability when the estimated amount of total body water is used instead of body weight may result from statistical artifacts associated with regression analysis.