<p>Including women in research and collecting and disaggregating data on sex is an ethical imperative. However, increasingly gender identity is being prioritised over sex in data collection and language which has ethical implications. In this paper, the authors share their experiences as study participants; a health consumer advocate, patient research advisor, and lay researcher; and academic researchers of engaging with researchers, Human Research Ethics Committees (HRECs), university ethics offices, and editors and reviewers of journals regarding data collection and communication on sex and gender identity. We argue that HRECs, researchers, and publishers must carefully consider the implications of omitting data collection on sex, mandatory and universalising gender identity questions and use of desexed language. We also propose that reduced data collection and disaggregation by sex, universal imposition of gender identity, and use of desexed language in research is decreasing data quality, reducing the willingness of some to participate in research and is culturally imperialistic. Recommendations for HRECs are made and research needs in relation to sex and gender identity are outlined. Respect for women in the conduct of research requires their sex-related experiences and needs are considered and therefore that data on sex is appropriately collected and reported upon.</p>