Albertazzi Paola, Bottazzi Mirella, Steel Susan A
Centre for Metabolic Bone Disease, University of Hull, Hull HU3 2RW, UK.
Contraception. 2006 Jun;73(6):577-83. doi: 10.1016/j.contraception.2006.02.004. Epub 2006 Apr 27.
Depot medroxyprogesterone acetate (DMPA) suppresses pituitary gonadotrophin output, thus, suppressing ovulation. Estrogen production from the ovary is also strongly inhibited, and the resulting estrogen deficiency has a detrimental impact on bone. Depot medroxyprogesterone acetate may be particularly detrimental in young women, as it may impede attainment of peak bone mass, and switching to a different contraceptive is recommended. However, the effect of sequential use of DMPA with other contraceptives in this age group has not been investigated.
This was a cross-sectional analysis of 218 DMPA users who were 20 years or older (mean, 31 years, +/-8.9 SD) at the time of bone mineral density (BMD) estimation. The majority of women had used one or more contraceptive beside DMPA. The most commonly used alternative contraceptive was the oral combined pill (OCP). It was used by 65% of women (n=143) and for an average duration of 6 years. A logistic regression model was used to estimate the association between potential risk factors and low bone mass.
The prevalence of low bone mass at either hip or spine (T< or =1) was 41%. The prevalence of a T score below -2.5 was 5%, and 45% of women had already sustained one fracture. Younger age was associated with higher BMD [odds ratios (ORs), 0.054; 95% confidence interval (CI), 0.007-0.431]. However, this protective effect of age was lost once the interaction between the duration of both DMPA and OCP was introduced into the model (OR for low BMD, 1.42; 95% CI, 1.09-1.8). The use of DMPA first before ever use of OCP was particularly detrimental to BMD (OR, 3.94; 95% CI, 1.08-14.0). On the contrary, body mass index was positively associated with BMD (OR, 0.86; 95% CI, 0.8-0.9). No other demographic or anamnestic variables significantly predicted the presence of low BMD in this group of young women. This group of DMPA users appear to be at a very high risk of both low BMD and fractures, possibly independently of DMPA use. This needs to be considered when writing guidelines for risk assessment.
The use of DMPA before achievement of peak bone mass may be particularly detrimental to bone, but switching DMPA with the OCP in these women does not seem to confer specific benefit in terms of bone density. This needs to be taken into consideration when a change in contraceptive is considered purely for the sake of bone protection.
醋酸甲羟孕酮长效注射剂（DMPA）可抑制垂体促性腺激素的分泌，从而抑制排卵。卵巢雌激素的分泌也会受到强烈抑制，由此产生的雌激素缺乏会对骨骼产生不利影响。醋酸甲羟孕酮长效注射剂对年轻女性可能尤其有害，因为它可能会阻碍骨量峰值的获得，因此建议改用其他避孕方法。然而，该年龄组中DMPA与其他避孕药序贯使用的效果尚未得到研究。
这是一项对218名使用DMPA的女性进行的横断面分析，这些女性在进行骨密度（BMD）评估时年龄在20岁及以上（平均31岁，标准差±8.9）。大多数女性除了使用DMPA外，还使用过一种或多种避孕药。最常用的替代避孕药是口服复方避孕药（OCP）。65%的女性（n = 143）使用过该药物，平均使用时长为6年。采用逻辑回归模型来估计潜在风险因素与低骨量之间的关联。
髋部或脊柱骨量低（T≤1）的患病率为41%。T值低于 -2.5的患病率为5%，45%的女性已经发生过一次骨折。年龄较小与较高的骨密度相关[优势比（ORs）为0.054；95%置信区间（CI）为0.007 - 0.431]。然而，一旦将DMPA和OCP的使用时长之间的相互作用纳入模型，年龄的这种保护作用就消失了（低骨密度的OR为1.42；95% CI为1.09 - 1.8）。在首次使用OCP之前先使用DMPA对骨密度尤其有害（OR为3.94；95% CI为1.08 - 14.0）。相反，体重指数与骨密度呈正相关（OR为0.86；95% CI为0.8 - 0.9）。在这组年轻女性中，没有其他人口统计学或既往史变量能显著预测低骨密度的存在。这组使用DMPA的女性似乎同时面临低骨密度和骨折的高风险，这可能与是否使用DMPA无关。在制定风险评估指南时需要考虑到这一点。
在骨量峰值尚未达到之前使用DMPA可能对骨骼尤其有害，但在这些女性中将DMPA换成OCP在骨密度方面似乎并没有带来特别的益处。当纯粹为了保护骨骼而考虑更换避孕药时，需要考虑到这一点。
