You know, like "soccer moms" and "security moms." But it's distractingly oxymoronic: if you use birth control, it's to avoid motherhood.
Except... soccer moms don't play soccer. And security moms — is that really a famous term? — aren't providing the security. The "mom" part of the term is about... well, what is it about? It's what patronizing politicos call the women who they imagine don't think, but emote and intuit their way through elections. Or perhaps, in part, it's that women who are mothers are concerned about the children. In that light, a "birth control mom" isn't a woman who wants her birth control devices. As a soccer mom likes to see the kids playing soccer, a birth control mom likes to see the kids using birth control, when they fuck, which they will do... you can't stop 'em... or if you think you can, you might already be a Santorumite.
UPDATE: After a lefty blogger criticizes this post, I expose his phallocracy.