Don’t automatically blame the woman. I’ve only known one woman who ever did this. In her case, it was self-defense as her perv of a husband was using pregnancy as a tool to try to control her.
I’ll definitely echo what other people are saying. This marriage would be in grave trouble. There are trust issues, possibly on both sides. If she is using ABC behind his back, then she doesn’t trust him enough to tell him she’s using it, and if he objects to come up with him with a method of prevention, which she obviously desires; if she’s not using it, he doesn’t trust her.
If the issue is he wants kids and she doesn’t that opens up a whole 'nother matter in the marriage too.