I won't disagree with you, except maybe to point out I don't think it's necessarily just biological, but psychological/physiological gender as well that causes

I won't disagree with you, except maybe to point out I don't think it's necessarily just biological, but psychological/physiological gender as well that causes the difference. There is some evidence, though last I checked inconclusive, that gender identity has a fairly strong relation with certain brain structures. I don't think it would be surprising that these differences also cause people to gravitate towards certain interests. Not to say it's always 100% going to make them go towards those interests, before anybody accuses me of making that claim, but it's fairly apparent as far as I'm concerned that even given equal opportunity, people of different genders aren't attracted to the same fields in equal proportion. Gender in multiple senses determines how the brain develops, so it would be surprising if these fields were demographically equal. I think making an equal opportunity approach is definitely the right thing, but equal outcome I think ends up holding people back and forcing others into fields they won't enjoy. It's working not on the idea of cultivating individual people's passions but forcing them to fit some ideal. In any case, though, I don't think any of this means that women should be disproportionately affected by having a child. I'm willing to buy the argument that it's societally caused due to expectations and men taking less time off than women for their children.