Hadji P, Ziller V, Kalder M, Gottschalk M, Hellmeyer L, Hars O, Schmidt S, Schulz K-D
Department of Gynecology, Gynecological Oncology and Endocrinology, Philipps University Marburg, Marburg, Germany.
Climacteric. 2002 Sep;5(3):277-85.
Reproductive factors such as parity and breast-feeding may be associated with low bone mass and osteoporotic fractures in later years. In this study, os calcis quantitative ultrasonometry was used to elucidate the relationship between parity, lactation and bone mass in postmenopausal women.
This was a comparison study using subsequent matched pairs analysis as well as multiple linear regression analysis. The study was carried out at five centers in Germany. The study included 2,080 postmenopausal women (age (mean +/- SD) 58.8 +/- 8.2 years), who were attending for routine check-up and in whom diseases and drug treatments known to affect bone metabolism had been excluded.
Women underwent quantitative ultrasonometry (QUS) measurement at the heel. Values of the ultrasonometry variables -speed of sound, broadband ultrasound attenuation and stiffness index -were calculated and compared for nulliparous and parous women and for women who had and had not breast-fed. Because of some significant intergroup differences, and to determine any effect of the number of live births and the duration of breast-feeding on ultrasonometry results, second analyses were undertaken using equally sized samples, matched for possible confounding variables such as age and body mass index (matched pairs). In these analyses, nulliparous women were compared with parous women, grouped according to number of live births, and women who had never breast-fed were compared with women who had breast-fed, grouped according to duration of breast-feeding. Furthermore, a multiple linear regression analysis was performed to examine the combined effects of reproductive factors on QUS variables.
No statistically significant associations were found between ultrasonometry variables and parity or breast-feeding, even after controlling for confounding variables in matched-pairs analysis or in a multiple linear regression analysis.
生育因素如产次和母乳喂养可能与晚年低骨量及骨质疏松性骨折有关。在本研究中，采用跟骨定量超声测量法来阐明绝经后女性的产次、哺乳与骨量之间的关系。
这是一项采用后续配对分析以及多元线性回归分析的比较研究。该研究在德国的五个中心开展。研究纳入了2080名绝经后女性（年龄（均值±标准差）58.8±8.2岁），这些女性前来进行常规体检，且已排除已知会影响骨代谢的疾病和药物治疗。
女性接受足跟部的定量超声（QUS）测量。计算超声测量变量——声速、宽带超声衰减和硬度指数的值，并对未生育和已生育女性以及曾哺乳和未哺乳女性进行比较。由于存在一些显著的组间差异，且为了确定活产次数和母乳喂养持续时间对超声测量结果的任何影响，进行了第二次分析，使用了大小相等的样本，并对年龄和体重指数等可能的混杂变量进行匹配（配对）。在这些分析中，将未生育女性与根据活产次数分组的已生育女性进行比较，将从未哺乳的女性与根据母乳喂养持续时间分组的曾哺乳女性进行比较。此外，进行了多元线性回归分析以检验生育因素对QUS变量的综合影响。
即使在配对分析或多元线性回归分析中对混杂变量进行控制之后，也未发现超声测量变量与产次或母乳喂养之间存在统计学上的显著关联。
