I'm a woman who was originally introduced to HN through Reddit and started reading about a year ago (this is a throw-away account that I will probably not use again.) I don’t really care about startups – I'm a physics graduate student planning on going into academia – but I do care about programming and tech. I have not yet been able to find an active online community that caters to these interests that I would describe as being "female-friendly." At HN, at least, sexist jokes are usually downvoted/discouraged because of their lack of content, which is more than I can say for Reddit. I generally enjoy HN except when the community decides to discuss gender, which it seems to do multiple times a week, even when it's only tangentially related to the article and despite it already having been beaten to death on this very site a million times over. These conversations invariably turn into, "Women: Does society screw them up or is there just something weird with their brains (on average of course, let's be PC here)? Dudes speculate." This is the most interesting topic to hackers, apparently.
I guess it's good to know that HN just feels like a woman-free space because it practically is, in contrast to sites like Reddit that feel that way even with ~2/5 of the users being female.