A few years ago, I started my postdoc in a prominent biology lab at a top U.S. university, supported by a prestigious fellowship. I thought I was on track to become a professor. Instead, I am one of a number of female postdocs to leave the lab prematurely in recent years because of my supervisor's sexist behavior and the toxic lab environment she created. (Yes, she-women can be sexist, too, though I initially thought there would be little chance of facing sexism in a female professor's lab.) I am still committed to pursuing a scientific career and am transitioning to another lab. But I am driven to share my story because tolerating or fighting sexism should not be a rite of passage for female scientists.