Femoral neck dimensions are unlikely to be associated with age at menarche.

Hip axis length (HAL) has been reported as an independent risk factor for hip fracture. Later puberty may increase bone size because of delayed epiphyseal fusion. We sought to identify associations between bone size at the proximal femur with age at menarche and other indices of growth such as stature. Femoral neck dimensions were measured from dual-energy X-ray absorptiometry scans of the proximal femur in a random sample of 203 premenopausal Caucasian women (age 20-30 years). There were no associations between age at menarche and HAL, femoral axis length (FAL) or femoral neck width (FNW). Age at menarche was associated with height (r = 0.2, p = 0.02). Variations in HAL, FAL and FNW do not appear to be related to age at menarche.