Well I don't know oop, I have a friend who had an abortion and regrets it because another friend who got pregnant at the same time ands kept the child is now her boss, the graduated together but the pregnant friend graduated pregnant summa cum laude. I think her regret is based on doubting her own ability to still have been successful( that was her main point in wanting an abortion, she'd talked to me about this plenty of times before the actual appointment) as opposed to actually wanting to have given birth. In other words, I think her regret is misplaced on the abortion itself as opposed to the reason WHY she got an abortion.
I just wonder the same about people who regret adoption. Is it because they think " hey I could have been a great parent" or that they simply wanted no one else to parent their child, even though they know they weren't ready to do it either so an abortion would have bene best in their case.