Warning: sex stereotyping ahead. It's supposed to be funny, folks; don't take it too seriously.
How can you tell that men, not women, designed the birth control pill? Simple. I figured it out after reading Malcolm Gladwell's What the Dog Saw, in which he comments that it is not biologically necessary that birth control pills have an "off" week to induce menstruation; it was part of the design so that the woman's cycle would be more normal. But what is "normal" about menstruating every month? Young girls don't, older women don't, some top athletes don't, and more importantly, women who are pregnant or intensely breastfeeding usually don't, either. Here's the scenario as I see it:
Male researchers Let's see. Women who are pregnant don't ovulate, so if we manipulate a woman's hormones so that we mimic pregnancy, she won't ovulate, and can't get pregnant. This means we could have sex whenever we feel like it, without any sacrifice on our part, leaving the entire responsibility on women for whether or not they get pregnant. Yee-haw! But we won't really mimic pregnancy, in which a woman doesn't menstruate for at least nine months and sometimes two years or more, because, well, because it's natural for a woman to menstruate every 28 days.
Female researchers Let's see. Women don't menstruate while pregnant, and often don't while lactating, so if we manipulate a woman's hormones so that we mimic pregnancy, she need only menstruate once every year or two. Yee-haw! This means could go two years without experiencing the mood swings, intense pain, and mess? Bring it on! Wait, you say we ought to design this pill so that the fake pregnancy miscarries every 28 days? You must be C-R-A-Z-Y!
