"We were always going to wait [until] after the baby," Simpson told UsMagazine.com Wednesday.
"We flirted around with different dates before I found out I was pregnant, and, thankfully, we didn't lock anything down. I want to enjoy the day," she said. "I'm glad we didn't make a deposit. ... I just didn't want to be stressed out. ... Now when I get stressed out, it's like 50 times worse. So I really want to enjoy that day and now I get to have my baby with me."
The couple have been engaged for a year. They have not disclosed their baby's gender or anticipated birth date.
Celebrity Couples of 2014 [PHOTOS]