U.S. Republican Vice Presidential candidate Sarah Palin shocked the first day of the party's national convention on Monday by announcing her 17-year-old daughter is pregnant.

The 44-year-old governor of Alaska said in a statement with her husband Todd that her daughter, Bristol, brought up with the news and made them realize she grows up faster than they had ever planned.

U.S. Republican vice-presidential candidate Alaska Governor Sarah Palin campaigns in Washington, Pennsylvania August 30, 2008. [Xinhua/Reuters Photo]

However, Palin said that she and her husband are "proud of Bristol's decision to have her baby and even prouder to become grandparents."

"As Bristol faces the responsibilities of adulthood, she knows she has our unconditional love and support," said the statement. "Bristol and the young man she will marry are going to realize very quickly the difficulties of raising a child, which is why they will have the love and support of our entire family."

The newly-selected VP candidate urged media to respect her daughter's privacy "as has always been the tradition of children of candidates."

The timing of statement was also concurrent with the starting day of the Republican National Convention, where McCain and Palin were expected to officially receive their nominations.

McCain's campaign told reporters that McCain has known about Bristol's five-month pregnancy before asking Palin to run with him.

The move was considered by U.S. media and political analysts as a way to dispel a rumor on liberal bloggers, saying that Palin faked her own pregnancy and pretended to have given birth in May to her fifth child, Trig, who was actually Bristol's child.

U.S. Republican vice-presidential candidate Alaska Governor Sarah Palin shakes hands as she campaigns in O'Fallon, Missouri August 31, 2008. [Xinhua/Reuters Photo]

(Xinhua News Agency September 2, 2008)