Logistically unfeasible (setting aside the entire "ethicality" issue).
The Chuz Liferz who hang out in front of Planned Parenthood waving placards could claim to be the putative "impregnaters" of every woman who walked through the door.
They could get court injunctions to stop these abortions; by the time DNA testing was done (not sure if fetal DNA testing is even a reality at this time) which proved they were not, it might be too
late for an abortion.
The fact is, a man does not
know he has impregnated a woman unless she chooses to
tell him so.
And even if he learns that a woman he's had sex with is in fact pregnant, he has no guarantee that he is the "father". She may not even know.
Ever heard the old saying "Mommy's baby. Daddy's, maybe"... ?
Until DNA testing, there was no way- ever- for a man to prove that a child was his.
I still don't think there's any way for a man to prove that he is responsible for a pregnancy, unless and until a child is actually born.
Let's say, hypothetically, that there
is, though; let's say they can stick a needle into a fetus, extract some of its DNA, and test it to see if it matches with the putative father's.
Any male anti-choice activist could step up and claim to be the father of untold numbers of fetuses, tying things up in court until it was too late for these women to get abortions.
When DNA testing proved he was lying, one of his cronies could simply step up and say, "Whoops, actually
I'm the father", putting the woman through testing over and over again until the very day she gave birth (at which point the anti-choicers would lose interest in her and her child entirely, since it's only about control over females and abrogation of females' human rights. Mission accomplished).
It is not feasible for women to have freedom of reproductive
choice, if the will of men trump the will of women when it comes to women's reproductive functions.
It's utterly senseless, frankly.
It is infeasible for men to attempt to control women individually in this manner. The logistics would defeat them; ultimately, women would circumvent any such laws by simply not telling their sex partner that they were pregnant, and lying about who their sex partners were.
Men would have a better shot at outlawing abortion entirely, than at this.
Not that they'll ever be able to outlaw abortion, either, but it's a more realistic goal than passing legislation which states that individual women need their sex partners' permission in order to end an unwanted pregnancy.
There is no way that would ever work, from a practical perspective.
It would not prevent one single, solitary woman from ending an unwanted pregnancy.
It would be too easy to circumvent.
