Plenty of research has examined how getting an abortion affects women's mental health. (In short, it doesn't, though individual circumstances vary enough that universal statements about women's reactions can be misleading.)
But what about those who want an abortion, but can't get one? Like S., a woman the New York Times Magazine interviewed. S. was 24 when she first found she was pregnant and decided to get an abortion. Click the link to read about her attempts to get the procedure, including one unwitting visit to a clinic where a nurse gave her an ultrasound and told her, "Look! Your baby is smiling at you."