Women are underrepresented in leading medical positions and academia. The gender-gap in authorship of congenital heart disease (CHD) publications remains unknown. As determinants of gender equity in this field are poorly characterised, we aimed to quantify and characterise publications in CHD and to assess factors associated with female representation in research.We identified 35 118 CHD publications between 2006 and 2015 for which author gender could be ascertained. Overall, 25.0% of all authors were female. Women accounted for 30.2% and 20.8% of all first and senior authorship positions with great geographic heterogeneity. While globally female first and senior authorship increased by 0.8% and 0.6%/year, some geographic regions showed no improvement in gender representation. Significant predictors of female first authorship on logistic regression analysis were country gross domestic product, human development index, gender inequality index and a female senior author (p<0.0001 for all). Publications with a female lead author tended to be published in journals with a higher impact factor (IF) and to attract more citations compared with those with a male author. Mixed gender authorship was associated with higher IF and number of citations. Women were less disadvantaged when the analysis was confined to original research.While modest improvement in female authorship over time was noted, women remain underrepresented in contemporary academic CHD. Manuscripts with mixed gender authorship had higher IF and more citations. The main predictor of female first authorship was a female senior author. These data should inform policy recommendations regarding gender parity.