Scientific conferences are important places to develop professional skills, find mentors, and seek employment opportunities. In order to better understand the benefits of these kinds of networking opportunities, multiple studies have evaluated how well STEM (science, technology, engineering, mathematics) conferences include white women, women and men of color, and people in other marginalized groups, whether as members of the Scientific Organizing Committee, as session chairs, or as presenters in the topical oral sessions. For example, a study of speakers at the fall American Geophysical Union (AGU) meetings reported that women submitted 32% of all abstracts and that women opted for poster presentations more often than did men. It was also reported that male session conveners allocated invited abstracts and oral presentations to women less often and below the proportion of women first authors. In this study, we examined gender demographics at the annual Lunar and Planetary Science Conferences (LPSCs) between 1999 and 2017. Gender presentation of authors of abstracts and oral presenters (>28,600 names!) at these 18 LPSCs were inferred using available public information, such as photographs and personal and professional bios. Almost 97% of the names were assigned “M” (male) or “F” (female)”; the inferred gender of the remaining names could not be determined by the above methods. Assessment of the inferred gender of speakers shows that, for most LPSCs since 1999, there were more male speakers than female speakers (as a function of attendance). From 2013–2017, however, the percentages of male and female attendees with talks were nearly identical. The difference in the percentage of female speakers at recent LPSCs compared to AGU meetings may be due to the way the LPSC is organized: LPSC has a central organizing committee, whereas AGU has separate session organizers. Our data also show that men are more likely to submit multiple 1st-author abstracts. We recommend that all conferences, including LPSC and the meeting of the Division of Planetary Science (DPS), collect self-reported demographic information on all presenters. This would avoid the problems with inferring gender (see Strauss et al., this conference) and enable studies for axes of diversity besides gender, such as race. It would be of particular interest to examine presentation statistics at DPS meetings and the European Planetary Science Congress (EPSC) since DPS uses an organizational format similar to that of LPSC while EPSCs are organized more like meetings of the AGU.