Well it's not just pure sexism that would make an investors or co-founders nervous about a pregnancy. If I was starting a venture with capital for 10 months of runway, and my co-founder told me that they (or their spouse) was 3 months pregnant - well I would be happy for them personally, but I definitely would be concerned about our venture. I think anybody in their right mind would be concerned because you know they will have to take at least some time off for the birth - then who knows how they will feel about working after that. Maybe they'll be driven, maybe they'll decide they need to stay home with their new child. It's pretty tough to say, nobody knows for sure how they will feel. It's not something you really want to be dealing with while getting a company off the ground.

That's no excuse for the rude, sexist comments made in the article, though.