Menopause, reproductive life, hormone replacement therapy and bone phenotype at age 60-64: a British birth cohort
Osteoporotic fractures are a common cause of morbidity and mortality in older women and one of the main risk factors is low bone mineral density (BMD). The MRC National Survey of Health and Development, a birth cohort study started in 1946 and followed up regularly, enabled the research team to investigate whether timing of menopause and the length of reproductive life (the number of years between age at menarche and age at menopause), measured prospectively rather than relying on long-term recall, were associated with BMD, bone size and strength measured at age 60-64, long after most women have stopped having periods. We measured areal BMD at the hip and spine using dual-energy x-ray absorptiometry (DXA); and trabecular volumetric BMD (the spongy inner core of bone) at the wrist, and cortical volumetric BMD (the outer hard shell of bone), bone size and strength at the mid-forearm using peripheral quantitative computed tomography (pQCT). We found that women with a later natural menopause or a longer reproductive life had greater trabecular volumetric BMD and areal BMD in their early sixties than those who had an earlier natural menopause or a shorter reproductive life. There was no association between age at hysterectomy and BMD. Women who used HRT for longer had greater cortical volumetric BMD and areal BMD, bone size and strength.
Kuh D, Muthuri S, Cooper R, Moore A, MacKinnon K, Cooper C, Adams JE, Hardy R, Ward KA
J Clin Endocrinol Metab. 2016 Jul 29:jc20161828