Zolciak, 35, announced in June she is pregnant with her fifth child.
"I'm having twins and I couldn't be more excited. I was completely shocked. I had no idea. It was a natural conception but twins do run in the family, so I guess I shouldn't have been surprised," she told E! News.
"I can't believe I am going to be a mom to six children, it's going to be very busy but it's a dream come true."