A spokesman for Romijn, 35, and O’Connell, 34, confirmed the news Monday morning.
A source reveals, “Jerry couldn’t be happier about becoming a dad.”
The babies will be the first children for the pair. The couple got married in Los Angeles in July 2007.
Rebecca was married to actor John Stamos from September 1998 to March 2005.
UPDATE: People reports that the babies will be girls and were conceived without the help of in vitro fertilization or the fertility drug Clomid.