I'm sorry, and maybe someone can explain it to me, (I'm sure someone will), but in my world, if someone is using birth control of any kind, it means that one or both of the people in the relationship do not choose to reproduce at that time. If both people are healthy and want a child, then why use birth control of any kind.
Once the cells get together... the horse is out of the barn. Then the only choices for the partner who did not want to reproduce are to bring up the subject of abortion or accept the event and change their outlook/life plans/responsibility level etc..
If everybody could "get into the game" and become a responsible hard working parent and mate the day after the pregnancy test results, then it would be great. But in the world today there are so many young people who have one or more children without the love, resources or steadiness that they deserve. That is bad for the child, the parents and society.
I know that social decorum dictates that you always have a polite and positive response when someone tells you, "I'm pregnant". But honestly, I know many of you, after the conversation, say or think to yourself, "... she's (he's, they're) nowhere near ready to have a kid."
Just thinking outloud.
Pete