Tiffani Thiessen Laments Last 20 Pounds Of Baby Weight (PHOTOS)

09/16/2010 05:09 pm ET | Updated May 25, 2011

Tiffani Thiessen admits she hasn't had an easy time shedding the baby weight since giving birth to daughter Harper Renn in June.

"I'd love to be my size again but my body is just not that way," she told People. "It doesn't work that way for me and I'm okay with that."

Tiffani gained 50 pounds while pregnant and is still working on losing the last 20, which are "really super stubborn."

"When you're running on four hours of sleep it's a little hard to get motivated but I am definitely trying," she told People. "I'm going to the gym three to four times a week and I started to run again."

Here's Tiffani at a Crest Pro-Health event Wednesday and a Rachel Roy presentation at Fashion Week on Tuesday.