Edmonds shares 14-month-old daughter Aspen with husband Jim Edmonds, and announced in December that she's pregnant with twin sons. Her baby boys are due in June.
"As I was filming the season 12 reunion I knew in my heart I was done; this wasn't my place anymore," the star said.
"I was only 5 weeks pregnant when I filmed the reunion and I was already exhausted. I knew that I was going to have a long pregnancy growing the twins and it would be next to impossible to film."
"I'm sad to leave RHOC, I'm sad to leave Orange County. I wasn't ready to make this decision for another year but I felt it was time now," she added. "I know this is what I must do. I must focus on my family and my pregnancy."
Edmonds said she and Jim, a former MLB player who now serves as a Fox Sports Midwest broadcaster, will relocate to the Midwest.
Jim is dad to four other children, including 10-year-old Landon and 7-year-old Sutton.
"Lastly but not least importantly, I wanted to spend more time with my husband during baseball season and more time with my two young step-kids who live full-time in St. Louis," Edmonds said.
"So Jimmy and I have decided to dig our roots into the midwest as we begin to build our dream home for our rapidly expanding family."
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