Showbiz
Rex Features
US shock-jock Howard Stern, who is a close friend of the actress and her husband Jerry O'Connell, made the announcement on his Monday radio show.
The babies' names and weights have not been released.
Scream 2 star O'Connell revealed last August that he was already feeling protective of his unborn daughters.
"Just the fact that they're girls, you know?" he told Us Weekly. "I don't want them to date. They're only allowed to date men who run countries. They're only allowed to date men who are heir to throne or are currently running a nation."
The actor also joked that the couple may call one of their children after Romijn's idol, saying: "My wife is very big Dolly Parton fan, so that will probably be one of the names."
Related Stories
Ten Things About...
Ten Things About... Ridley ScottWe find out ten fast facts about the English producer and director.
Interviews
'ANTM' Laura LaFrate interviewThe runner-up speaks with Digital Spy about the contest and the other models.
Fashion & Beauty
Jessie J: 'I can get my bum out more'The 'Price Tag' singer says that she "was a girl, this year a woman".
Celeb Birthdays
Celebrity Birthdays: Clarkson, Tatum, moreFind out which famous faces will celebrate birthdays over the coming seven days.
