The 27-year-old actress gave birth to her first child, a daughter, with husband Ryan Reynolds in December.
During her pregnancy, Lively wowed with incredible ensembles which both flattered and highlighted her blooming figure.
The website's maternity style expert explained Lively's outfit choices helped other pregnant women understand that they have options when it comes to dressing a bump.
"Forget everything you think you know when it comes to maternity style. You don't need to hide in black leggings and an over sized top for nine months," Robin Otto said.
Other names to feature on the best-dressed bumps list include Kate Middleton, Kristen Bell, Carrie Underwood and Kourtney Kardashian.