Although previous studies have evaluated how the proportion of women in orthopaedic surgery has changed over time, these analyses have been limited by small sample sizes, have primarily used data on residents, and have not included information on growth across subspecialties and geographic regions. We used the National Provider Identifier registry to ask: How have the (1) overall, (2) regional, and (3) subspecialty percentages of women among all currently practicing orthopaedic providers changed over time in the United States? The National Provider Identifier Registry of the Centers for Medicare and Medicaid Services (CMS) was queried for all active providers with taxonomy codes pertaining to orthopaedic subspecialties as of April 2020. Women orthopaedic surgeons were identified among all physicians with subspecialty taxonomy codes. As all providers are required to provide a gender when applying for an NPI, all providers with queried taxonomy codes additionally had gender classification. Our final cohort consisted of 31,296 practicing orthopaedic surgeons, of whom 8% (2363 of 31,296) were women. A total of 11,714 (37%) surgeons possessed taxonomy codes corresponding with a specific orthopaedic subspecialty. A univariate linear regression analysis was used to analyze trends in the annual proportions of women who are active orthopaedic surgeons based on NPI enumeration dates. Specifically, annual proportions were defined using cross-sections of the NPI registry on December 31 of each year. Linear regression was similarly used to evaluate changes in the annual proportion of women orthopaedic surgeons across United States Census regions and divisions, as well as orthopaedic subspecialties. The national growth rate was then projected forward to determine the year at which the representation of women orthopaedic surgeons would achieve parity with the proportion of all women physicians (36.3% or 340,018 of 936,254, as determined by the 2019 American Medical Association Physician Masterfile) and the proportion of all women in the United States (50.8% or 166,650,550 of 328,239,523 as determined by 2019 American Community Survey from the United States Census Bureau). Gender parity projections along with corresponding 95% confidence intervals were calculated using the Holt-Winters forecasting algorithm. The proportions of women physicians and women in the United States were assumed to remain fixed at 2019 values of 36.3% and 50.8%, respectively. There was a national increase in the proportion of women orthopaedic surgeons between 2010 and 2019 (r2 = 0.98; p < 0.001) at a compound annual growth rate of 2%. Specifically, the national proportion of orthopaedic surgeons who were women increased from 6% (1670 of 26,186) to 8% (2350 of 30,647). Assuming constant growth at this rate following 2019, the time to achieve gender parity with the overall medical profession (that is, to achieve 36.3% women in orthopaedic surgery) is projected to be 217 years, or by the year 2236. Likewise, the time to achieve gender parity with the overall US population (which is 50.8% women) is projected to be 326 years, or by the year 2354. During our study period, there were increases in the proportion of women orthopaedic surgeons across US Census regions. The lowest growth was in the West (17%) and the South (19%). Similar growth was demonstrated across census divisions. In each orthopaedic subspecialty, we found increases in the proportion of women surgeons throughout the study period. Adult reconstruction (0%) and spine surgery (1%) had the lowest growth. We calculate that at the current rate of change, it will take more than 200 years for orthopaedic surgery to achieve gender parity with the overall medical profession. Although some regions and subspecialties have grown at comparably higher rates, collectively, there has been minimal growth across all domains. Given this meager growth, we believe that substantive changes must be made across all levels of orthopaedic education and leadership to steepen the current curve. These include mandating that all medical school curricula include dedicated exposure to orthopaedic surgery to increase the number of women coming through the orthopaedic pipeline. Additionally, we believe the Accreditation Council for Graduate Medical Education and individual programs should require specific benchmarks for the proportion of orthopaedic faculty and fellowship program directors, as well as for the proportion of incoming trainees, who are women. Furthermore, we believe there should be a national effort led by American Academy of Orthopaedic Surgeons and orthopaedic subspecialty societies to foster the academic development of women in orthopaedic surgery while recruiting more women into leadership positions. Future analyses should evaluate the efficacy of diversity efforts among other surgical specialties that have achieved or made greater strides toward gender parity, as well as how these programs can be implemented into orthopaedic surgery.