When I studied computer science at Duke University in the first half of the 1980s, I had professors who treated women differently than men. I kind of got used to it. At Microsoft, I had to use my elbows and make sure I spoke up at the table, but it was an incredibly meritocratic place. Outside, in the industry, I would feel the sexism. I'd walk into a room and until I proved my worth, everyone would assume that the guy presenting with me had credibility and I didn't.

I felt suicidal. I couldn't stop crying. I remember thinking, wouldn't it be great if the car crashed and I died?

I went to business school, and I went straight from that to a nine-year career at Microsoft. Eventually, I ran a big chunk of the consumer products division for Microsoft.Then I left with the birth of our first daughter because Bill and I both wanted to have a few kids.

The biggest pieces of work that we do are vaccines, because those save lives, and also family planning. Because if a woman can space the births of her children, it changes everything for her health and her child's health.

Childbearing, I mean, if there's no place to go to deliver your baby, then you're the one that's delivering in those unhealthy circumstances. Or if you can't get access to family planning, your chances of surviving and being able to bring your kids up if they come one right after the other, that locks you into a cycle of poverty.

I care much more about saving the lives of mothers and babies than I do about a fancy museum somewhere.

[Bill Gates] wanted me to stay working at Microsoft, but I didn't think he could be CEO and we could have the family life that we both had growing up, which is what we envisioned. I knew I would go back to work at some point later to some profession. I just didn't know what.