Jessica Simpson Shows Off Post-Baby Body: Jessica Simpson six months and a hundred pounds after giving birth to Birdie Mae. Jessica Simpson Shows Off Post-Baby Body: Jessica Simpson six months and a hundred pounds after giving birth to Birdie Mae. In a tweet, she says she’s “proud to feel like [herself] again.” A source said that the mother of three has been working out, walking, and eating healthy to get back in shape. Simpson is famous for gaining weight during her pregnancies and then taking it off again. This time she says she gained over 100 pounds but has lost most of it over the last 6 months.