As a woman and professional developer, my reason for not participating in OSS is lack of time / energy to devote to it. I have other priorities for the hours I'm not at work, such as going to the gym, cleaning, cooking / baking, spending time on family and romantic relationships, reading, etc.
I assume these priorities have been shaped by my upbringing and culture, and in my experience they differ from average American male priorities. I feel less pressure to achieve a prestigious career or a high level of competence in a hobby, but more pressure to keep a clean attractive home, to spend time on my appearance, to help organize / cook for family events, and to accommodate / support my SO's career goals.
Personally I don't resent the time spent on housework, it is my choice to change the sheets and vacuum regularly rather than nagging my SO or tolerating a messy home, but I do believe these choices are the result of my upbringing as a "girl" and the cultural pressure to be "feminine" and a "homemaker" even, or maybe especially, while pursuing a career in a male-dominated field.