Effects of Reproductive Factors on Bone Mineral Densitometry

Aim: To determine the effects of reproductive factors on bone mineral density (BMD) in postmenopausal women. Materials and Methods: A total of 1196 postmenopausal women with BMD (g/cm2) measurements at lumbar vertebra (LS) and femur neck (FN) were enrolled. Demographic, reproductive characteristics and Body Mass Index (BMI) of patients were defined. In order to define BMD related factors, multiple regression analysis was employed. Results: Main results were as follows: mean age= 59.97±8.56 yrs; weight= 73.49±13.06 kg; BMI= 29.25±5.22kg/m², age of menarche= 14.00±1.64 yrs; number of deliveries 4.22±2.09; total breastfeeding duration= 60.77±38.80 months; number of breastfeeding per day= 8.23±3.91; menopausal age= 47.12±4.22 yrs; duration of menopause= 12.80±9.10 yrs; LS BMD= 0.993±0.171 gr/cm2; FN BMD 0.844±0.14 gr/cm2. There were negative correlations between LS BMD and FN BMD values and age, menopause duration, total breastfeeding duration, and number of breastfeeding per day. There were positive correlations between LS and FN BMD values, and weight and BMI scores. Additionally, there were negative correlations between LS and FN BMD values, and age of menarche and number of deliveries. In linear stage regression analysis, weight, number of breastfeeding per day, postmenopausal duration, duration of total breastfeeding and age of menarche were defined as the most significant predictors for LS BMD, whereas weight, postmenopausal duration and number of breastfeeding per day were defined as the most significant predictors for FN BMD. Conclusion: LS and FN BMD in postmenopausal women are related to reproductive factors, so reproductive factors should also be considered in the evaluation of risk factors in postmenopausal women. (Turkish Journal of Osteoporosis 2012;18:8-12)