Guatemala's congress has voted to raise the minimum legal age for girls to marry to 18 from 14.

The unicameral congress voted 87 to 15 to approve the change, which had been urged by children's rights groups. However, legislators inserted a clause saying 16-year-old girls can marry with a judge's authorization in some cases.

Males are allowed to marry at age 16.

Congressman Leonel Lira says the bill will treat sex with underage youths as a form of rape.

UNICEF expert Juan Quinonez says there have been about 4,000 marriages a year in Guatemala involving girls ages 15 to 19. He adds that 4,700 girls from age 10 to 14 get pregnant every year.