Ekroos Sofie, Toffol Elena, Heikinheimo Oskari, Haukka Jari, Arvas Mikko
Faculty of Medicine, Medicum, University of Helsinki, Helsinki, Finland.
Research and Development, Finnish Red Cross Blood Service (FRCBS), Vantaa, Finland.
Eur J Epidemiol. 2025 Jul 10. doi: 10.1007/s10654-025-01272-3.
The WHO aims to reduce iron deficiency anaemia globally. Use of modern hormonal contraception (HC) could offer protection against anaemia in premenopausal women, but population-level effectiveness is unclear. We aim to quantify the effect of HC on anaemia. This nested case-control study includes over half the fertile-aged female population of Finland in 2017. Data on HC use from the national Prescription Center were combined with data on anaemia diagnosis from national care registries. Cases (anaemia diagnosis during follow-up, 2019-2020) were matched with up to five controls by age and municipality. After calculating the minimally sufficient adjustment set, adjusted odds ratios were derived in a conditional multivariable regression model accounting for matching. 3 100 cases of anaemia were matched with 13 143 controls. The minimally sufficient adjustment set included age, education level, obesity, abnormal uterine bleeding, and cancer. Compared to non-users of HC, risk of anaemia was lower in users of combined oral contraceptives containing ethinylestradiol (0·74 [0·66-0·83]) or oestradiol (0·49 [0·35-0·68]), progestin-only oral contraceptives (0·42 [0·35-0·51]), LNG-IUDs (0·64 [0·43-0·94]), and contraceptive vaginal rings (0·68 [0·49-0·94]). Individual product effects ranged from 0·77 [0·66-0·90] for drospirenone and ethinylestradiol to 0·40 [0·32-0·48] for desogestrel-only. Benefits of HC use extend to anaemia protection on population level. Anaemia protection should be included in guidelines on HC to support clinical decision making.
世界卫生组织旨在在全球范围内减少缺铁性贫血。使用现代激素避孕方法（HC）可能为绝经前女性预防贫血提供保护，但在人群层面的有效性尚不清楚。我们旨在量化HC对贫血的影响。这项嵌套病例对照研究纳入了2017年芬兰超过一半的育龄女性人口。来自国家处方中心的HC使用数据与国家医疗登记处的贫血诊断数据相结合。病例（2019 - 2020年随访期间的贫血诊断）按年龄和直辖市与多达五名对照进行匹配。在计算出最小充分调整集后，在考虑匹配因素的条件多变量回归模型中得出调整后的比值比。3100例贫血病例与13143名对照进行了匹配。最小充分调整集包括年龄、教育水平、肥胖、异常子宫出血和癌症。与未使用HC的人群相比，使用含乙炔雌二醇（0.74 [0.66 - 0.83]）或雌二醇（0.49 [0.35 - 0.68]）的复方口服避孕药、仅含孕激素的口服避孕药（0.42 [0.35 - 0.51]）、左炔诺孕酮宫内节育器（0.64 [0.43 - 0.94]）和避孕阴道环（0.68 [0.49 - 0.94]）的人群患贫血的风险较低。各产品的个体效应范围从屈螺酮和乙炔雌二醇的0.77 [0.66 - 0.90]到仅含去氧孕烯的0.40 [0.32 - 0.48]。使用HC的益处扩展到人群层面的贫血保护。HC指南应纳入贫血保护内容以支持临床决策。
