I have tried constructing a pro-choice example similar to "Abortion is murder!" ("Forced pregnancy is slavery!"???), but it ended up pretty unconvincing. Hopefully someone can do better:

Leaving rape cases aside, the archetypal example is an unwanted teenage pregnancy due to defective or improperly used birth control or simply an accident. Forcing her into letting the embryo develop into a fetus and eventually into a human baby would likely make the woman significantly worse off in the long run, financially, physically and/or emotionally, so she should have an option of terminating the pregnancy.

An example a pro-life person thinks of: aborting a healthy fetus, possibly in the second trimester, as a habitual birth control method.