Early Discontinuation, Results Reporting, and Publication of Gynecology Clinical Trials From 2007 to 2020

OBJECTIVE: To characterize gynecology clinical trials over time, compare gynecology subspecialties, and analyze factors associated with early discontinuation, results reporting, and publication. METHODS: We conducted a cross-sectional analysis of all gynecology trials registered on ClinicalTrials.gov between 2007 and 2020 and their resulting publications. Trials were analyzed with descriptive, multivariable logistic, and Cox regression analyses. Primary exposure variables were trial funding and subspecialty. The three primary outcomes included early discontinuation, results reporting to ClinicalTrials.gov, and publication in a peer-reviewed journal indexed on PubMed. RESULTS: Of 223,690 trials registered on ClinicalTrials.gov between October 2007 and March 2020, only 3.7% focused on gynecology (n=8,174, approximately 3,759,086 participants). Subspecialties included reproductive endocrinology and infertility (n=1,428, 17.5%), gynecologic oncology (n=2,063, 25.2%), urogynecology (n=1,118, 13.7%), family planning (n=648, 7.9%), and other benign gynecology (n=2,917, 35.7%). Only 42.0% of completed trials disseminated results through results reporting and publication. Of all funding types, industry-funded trials were the most likely to be discontinued early (P<.001). Academic-funded trials were the least likely to report results (adjusted odds ratio [aOR] 0.38, 95% CI 0.30-0.50) but the most likely to publish (aOR 1.62, 95% CI 1.24-2.12). The number of reproductive endocrinology and infertility trials increased the most of any subspecialty between 2007 and 2020 (6.4% growth rate). Reproductive endocrinology and infertility and family planning trials were the most likely to be stopped early (reproductive endocrinology and infertility: adjusted hazard ratio [aHR] 2.08, 95% CI 1.59-2.71; family planning: aHR 1.55 95% CI 1.06-2.25). When completed, reproductive endocrinology and infertility trials were the least likely to report results (aOR 0.58, 95% CI 0.38-0.88). No significant differences were seen between subspecialties with respect to publication. CONCLUSION: Gynecology trials comprise only 3.7% of all clinical trials. The paucity of gynecology clinical trials aligns with decades of female underrepresentation in research. When completed, gynecology trials have poor dissemination. Our findings raise concern about bias in the performance, reporting, and publication of gynecology clinical trials.