Katherine spoke with Extra's Renee Bargh on the set of her new CBS legal drama Doubt recently, about her pregnancy, the challenges her bump poses during filming, and how daughters Naleigh and Adelaide are excited for their baby brother to arrive.

Katherine Heigl Talking Pregnancy & Doubt

Discussing her pregnancy, Katherine said "I feel great. It's been a really easy pregnancy and I had no idea what to expect... It's been kind of great." However, while she loves her baby bump, she is still getting used to some of the changes to her body. "Everything's just expanding. I don't understand why it has to go both ways" she added laughing, "What does my butt have to do with any of this?"

In Doubt, Katherine plays a defense attorney in love with a client accused of murder, which leads into some steamy love scenes. That has proved awkward with her emerging belly! "Just this basketball between us," she noted. quot;I'm like, 'I'm so sorry, so awkward!' and he was lovely, but you don't feel beautiful, really." She also shared, "It can get a little steamy, but with this situation [pointing to her belly] it can't get that steamy."

Doubt premieres Wednesday, February 15th, 2017 at 10/9C on CBS. Watch more of the interview on tonight's edition of Extra.