Jessica Simpson Says She Didn't Know She Could Get Pregnant While Breastfeeding: 'Wait, What?' As she makes her highly anticipated return to the music scene, Jessica Simpson is sharing anecdotes about some of the major changes in her private life that took place during her hiatus.

After 15 years away from music, Jessica Simpson kept her cool as her outfit slipped down as she performed a medley of her older songs.

While Simpson thought breastfeeding acting as a form of birth control, the mom of three was pleasantly surprised when she got pregnant with baby No. 2 just four months after she and ex-husband Eric Johnson welcomed their first child.