The actress, who shot to fame playing Jesse Spano in the TV series Saved By The Bell, revealed to followers on Twitter that she and husband Greg Lauren are expecting their first child together.
"In life there are moments you cherish forever and this is one of them," she wrote.
"Greg and I are so excited to be expecting our first child this summer. We couldn't be more grateful and overjoyed."
She later thanked followers for their congratulatory messages, saying: "My heart is full w all ur sweet good wishes. Grateful for ur support always!! Xo"
Berkley, who has penned a self-help book for teenagers called Ask Elizabeth, married artist and actor Lauren in Cabo San Lucas, Mexico in 2003.
Lauren is the nephew of fashion designer Ralph Lauren.
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