For the pill. Other devices are much higher, like 10% or even more.
And that is a per year failure rate, not a cumulative lifetime rate.
And that is if the contraceptive is always used properly.
The point is that many, many people have failures. And that many of them are not prepared to raise a child. So they turn to the backstop - abortion.
Contraceptive use fosters a mentality that sex has no consequences and that everyone should be doing it. This leads to abortion.
SD
I don't know. Lots of people using contraceptives are married and would raise the child if they got pregnant. We all know families, post Roe, with oops kids.
Even many of the unmarrieds would choose to keep the child or adopt it.
You are assuming every failure directly results in abortions. Not true.