The Star Trek actress, 36, and her artist husband are said to have become parents to their first child together, believed to be two boys.
According to E! Online, the couple "are both so excited".
A source says: "They are surrounded by family and friends. All that matters now to Zoe and her husband is that the babies are healthy."
The Mirror reports that Avatar actress Zoe had her children in an LA hospital on Monday (8 December).
Zoe, who is half Puerto Rican, told the September issue of Cosmopolitan For Latinas that she and Marco plan to speak Spanish to their children and raise them as bilingual.
She and Marco married in the summer of 2013, and Zoe confirmed she was pregnant in August in a rather unique way...
After accepting the ALS 'ice bucket challenge' from director friend James Gunn, which sees people throw ice cold water over their head for charity, Zoe immediately nominated Marco instead.
Turning to the side and rubbing her tummy, Zoe said: "I am accepting James Gunn's challenge to take on the ice bucket challenge. Obviously, I can't do it myself so I nominate my husband to take on the challenge!"
The next month, Zoe's friend and former Crossroads star Britney Spears let slip during an interview that Zoe was expecting twins!
When asked if they'd ever act together again, Britney replied: "Who knows? That's a very good idea. But she's pregnant with twins right now so I'm sure she's got a huge future ahead of her."
Many congratulations to the new parents!
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