Celebrity Parents Pregnant Billie Piper Feels Like a Sweating Sea Cow By Staff Author Published on August 17, 2008 01:00PM EDT When a woman becomes pregnant, she knows she’ll gain weight, but not all of them have the same problem as actress Billie Piper. The 25-year-old, who is expecting her first child this October with husband Laurence Fox,portrays a high-class hooker on the show Secret Diary Of A Call Girl and had to film scenes while trying to deal with her growing baby bump. In her role, Billie has to play a "sexually liberated, empowered young prostitute" but says she "unfortunately felt like a sweating sea cow" during filming. Billie, who shares that she’s had no cravings "other than wanting food constantly," which causes problems because of the "desire to just sit on my bum and stuff my face." However, she knows that’s "not conducive to work." Neither was her constant thirst and need for the bathroom, which was "really unhelpful when working to such a tight schedule." Luckily for Billie, the third series of the show will not begin filming until she has given birth this fall. Secret Diary Of A Call Girl is currently airing on Showtime On Demand. Source: OK! Magazine; Photo by Dan Woolier/WireImage.