"I will be delivering an addition to the first family," she said, smiling.
Palin, already seven months along, is due to give birth in mid-May, she said.
The news astonished reporters and others in the Capitol, who had no clue the governor was expecting. She simply doesn't look pregnant.
Palin said she already knows whether her baby is a boy or a girl, "but I don't want to say yet."
The 44-year-old governor and her husband, Todd, have four children: son Track, 18, and daughters Bristol, 17, Willow, 13, and Piper, 6.
Find Wesley Loy online at adn.com/contact/wloy or call him in Juneau at 1-907-586-1531.
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