No Association Between Intrauterine Contraceptive Devices and Musculoskeletal Hip Joint Pain

PURPOSE: To investigate the association between intrauterine device (IUD) use and hip pain, orthopaedic visits for hip pain, and arthroscopic hip surgery. METHODS: This was a retrospective cohort study of patients aged 18-44 years old using either IUDs or subdermal implants for contraception in a large commercial claims database (MarketScan) from 2012 to 2015. All patients had at least 12 months of continuous enrollment both before and after contraceptive placement. Patients with a history of hip pain or surgery were excluded. The primary outcome was new hip pain. Secondary outcomes included visiting an orthopaedic or sports medicine provider for a hip complaint, intra-articular hip injection, and arthroscopic hip surgery. Outcomes were analyzed with Cox proportional-hazard models. RESULTS: We identified a total of 242,383 patients, including 216,541 (89.3%) with IUDs and 25,842 (10.7%) with subdermal contraceptive implants. In time-to-event analysis, IUDs (vs implants) were not associated with increased risk of new hip pain diagnoses (hazard ratio [HR] 0.95, 95% confidence interval [CI] 0.87-1.03, P = .21). In contrast, both age (P < .001) and region (P < .001) were associated with increased risk of new hip pain. Similar results were seen for the secondary outcomes, including risk of orthopaedic visits for hip complaints (HR 1.06, 95% CI 0.83-1.35, P = .63), intra-articular injections of the hip (HR 0.94, 95% CI 0.63-1.41, P = .77), and hip arthroscopy procedures (HR 1.13, 95% CI 0.53-2.40, P = .75). CONCLUSIONS: In this study, we found no evidence that IUDs were associated with hip pain or surgery. LEVEL OF EVIDENCE: Level III, retrospective cohort.