That's not self-contradictory though -- it's just good old contradiction with a different position. So a person who only holds one of those beliefs would potentially be fine, as far as self-contradiction is concerned.
Besides, beliefs can be prioritized and in shades of gray. Somebody could value the life of an embryo very highly (going so far as to call it "inviolate" at times when they aren't carefully weighing their beliefs -- few people do that all the time, so we should allow for some lapses in precision), but still believe that certain other concerns trump it. After all, most pro-choice folks do value the life of an embryo highly, they just believe that the mother's rights over her body are even more important.
Besides, beliefs can be prioritized and in shades of gray. Somebody could value the life of an embryo very highly (going so far as to call it "inviolate" at times when they aren't carefully weighing their beliefs -- few people do that all the time, so we should allow for some lapses in precision), but still believe that certain other concerns trump it. After all, most pro-choice folks do value the life of an embryo highly, they just believe that the mother's rights over her body are even more important.