Abstract Aiming to explain and help reduce measured gender gaps in mathematics publications—a discipline where single anonymized peer review practices and men editors are still the norm—we study changes in authorships straddling a 2015 switch in peer review type and editor gender in the American Mathematical Monthly, one of the oldest mathematics journals in the United States. Our results show a significant increase in women authorships after the journal’s switch to a woman editor and double anonymized reviews, an increase deemed exceptional relative to growth trends in comparable journals operating under field standards (men editors along with single anonymized reviews). We leverage literature, data-based observations and our own findings to argue for the likely effects of editor gender and peer review type separately and together as it concerns both women and newcomer authorships. Our study, the first to our knowledge on editorial and peer review changes in mathematics, contributes to a small body of literature on the impact of equity practices in peer review in science and mathematics. It also serves to introduce work, methods, and open problems on measuring and reducing the global gender gap in science and mathematics.