Keep abortion safe and legal, in secret!
That’s my 100% facetious suggestion. Make a big show of outlawing abortion. Then, contact each woman who becomes pregnant but doesn’t want to be, and inform them that it’s actually still perfectly legal. Make them all swear to secrecy.
This would satisfy the anti-abortion people, plus it would make sure no one relied on the possibility of an abortion as a reason not to use contraception.
But seriously, though, I don’t think there is anything we could do to the law to prevent abuse. “Abuse”, as far as I’m concerned, would be when a couple habitually takes insufficient safe-sex precautions, just because abortion is an option. This is no different from someone thinking it’s okay to ride a motorcycle without their helmet, since with the miracles of modern medicine they might survive a crash.
Honestly, I think this is very rare. Nobody wants an abortion, it’s just that they want to delivery a baby even less. Lots of people have good reasons for this (a subjective statement, to be sure): they are too young to raise a child; they have unhealthy constitutions; they would rather finish school; they were impregnated by someone they don’t want to reproduce with.
Sure, there are cases of women who’ve had a kazillion abortions and keep going out having unsafe sex. Just as there are people who bike without helmets, skydive off of large rocks, and smoke. It’s just that we can’t let a couple of self-destructive cases interfere with the reproductive choice of the general public.
Legal action would be called for if the bulk of the suffering from these actions fell on society as a whole. As long as it falls on mainly on the individual, as it does with abortion, I think we have to pretty much trust with individual choice.
It is much better to inform people as much as possible. Tell them, in grim detail if necessary, that abortions are no fun. Sure, adults know this; do 15-year-old girls? (15-year-old boys should know too, but they probably aren’t going to care as much.) We do the same thing with Driver Education all the time. “Look at what happened to this Honda when the driver went for a spin after “just a few drinks”. Now imagine where the driver’s head is.” I’m not trying to be melodramatic; I’m just saying that the facts of unwanted pregnancy should be enough to discourage it. Especially when contrasted with something as simple as most forms of contraception.