The Monster's Ball star and her actor fiancé are having a baby boy, reports TMZ.
A source close to the couple claimed that the 46-year-old actress is at least three months pregnant.
She is said to have found out that she was expecting shortly after complaining that she felt sick at this year's Oscars ceremony.
Berry already has a daughter - Nahla, 5 - with her former partner Gabriel Aubry. The male model, who spilt from Berry in 2010, was involved in an altercation with Martinez last November following a custody disagreement, which left both men needing medical attention.
Earlier this week, the Oscar-winning actress and her fiancé confronted members of the paparazzi at LAX airport, Los Angeles.
Berry was filmed yelling and swearing at cameramen, who were trying to capture shots of her daughter, while Martinez is said to have lashed out at a photographer as the pair made their way to an awaiting car.
Berry's representative has not issued any formal comment on the incident.
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