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To characterize gynecology clinical trials over time, compare gynecology subspecialties, and analyze factors associated with early discontinuation, results reporting, and publication.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.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.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.

Most integral outer membrane proteins (OMPs) of Gram-negative bacteria, such as Escherichia coli , assume a β-barrel structure. The β-barrel assembly machine (Bam), a five-member complex composed of β-barrel OMP BamA and four associated lipoproteins, BamB, BamC, BamD, and BamE, folds and inserts OMPs into the outer membrane. The two essential proteins BamA and BamD interact to stabilize two subcomplexes, BamAB and BamCDE, and genetic and structural evidence suggests that interactions between BamA and BamD occur via an electrostatic interaction between a conserved aspartate residue in a periplasmic domain of BamA and a conserved arginine in BamD. In this work, we characterize charge-change mutations at these key BamA and BamD residues and nearby charged residues in BamA with respect to OMP assembly and Bam complex stability. We show that Bam complex stability does not correlate with function, that BamA and BamD must adopt at least two active conformational states during OMP assembly, and that these charged residues are not required for function. Rather, these charged residues are important for coordinating the activities of BamA and BamD to allow efficient OMP assembly. We present a model of OMP assembly wherein recognition and binding of unfolded OMP substrate by BamA and BamD induce a signaling interaction between the two proteins, causing conformational changes necessary for the assembly reaction to proceed. By analogy to signal sequence recognition by SecYEG, we believe these BamA-BamD interactions ensure that both substrate and complex are competent for OMP assembly before the assembly reaction commences. IMPORTANCE Conformational changes in the proteins of the β-barrel assembly machine (Bam complex) are associated with the folding and assembly of outer membrane proteins (OMPs) in Gram-negative bacteria. We show that electrostatic interactions between the two essential proteins BamA and BamD coordinate conformational changes upon binding of unfolded substrate that allow the assembly reaction to proceed. Mutations affecting this interaction are lethal not because they destabilize the Bam complex but rather because they disrupt this coordination. Our model of BamA-BamD interactions regulating conformation in response to proper substrate interaction is reminiscent of conformational changes the secretory (Sec) machinery undergoes after signal sequence recognition that ensure protein quality control.