No, when she became a Christian, Romney has explained his 'conversion' to the pro-life cause however I can't see into his heart to see if he's sincere or not but I have heard of many pro-choicers who have become pro-life and pro-lifers who have become pro-choice but once a person switches it's usually just one time, so I doubt that Romney will don the mantel of being pro-life only to switch back to being pro-choice.
The Mormon Church claims to be pro-life, even Harry Reid supposedly is pro-life so Romney's new pro-life views are in lockstep with his faith.