A lot of the comments here seem to focus on sexual harassment as The Issue. I wonder, though, about the issue of how close-knit and intimate start-up culture tends to be. There was a (flagged, dead) thread not terribly long ago where some married man had gotten his female co-founder pregnant and was looking for suggestions on how best to handle this big mess. Long hours, late nights and possibly no one else around in a close-knit, small social unit (aka a startup) is probably also a concern for some women, even if the men are all perfect gentlemen. They might not fess up to this angle but I think any concerns about this which one might normally have for work generally would be magnified by the type of intimate environment of a startup. An affair at work can lead to being fired (and sometimes other ugliness). So if someone has a brain and considers this to be a potential issue, it seems to me the wisest thing to do is not go there to begin with.
It's a great point. Women often have a lot more to lose in situations like this so may be extra wary. And the long hours late nights can be much more of an issue for single moms or moms in families where both parents are working. So it's challenging all around.
