AFP - Millions of girls worldwide are not going to school, an education gap that condemns them to lives of hardship and entrenches broader extreme poverty, a new report said Thursday.

The report, "Because I am a Girl: The State of the World's Girls 2012," was released in New York by Plan International on the United Nation's first International Day of the Girl.

"The estimated 75 million girls missing from classrooms across the world is a major violation of rights and a huge waste of young potential," the child poverty alleviation group said in launching the report.

A total of one in three girls is denied education, but Plan's report focuses especially on the 39 million girls aged between 11 and 15, right on the cusp of becoming young women, who are out of school.

The report -- which coincided with the news this week of a 14-year-old Pakistani girl gunned down for her criticism of Taliban campaigns against girl's education -- underlined the hugely positive impact that school can have on girls in poor countries.

"An educated girl is less vulnerable to violence, less likely to marry and have children when still a child herself, and more likely to be literate and healthy into adulthood -- as are her own children," Plan International CEO Nigel Chapman said.

"Her earning power is increased and she is more likely to invest her income for the benefit of her family, community and country. It is not an exaggeration to say educating girls can save lives and transform futures."

Plan called on global leaders to ensure a minimum of nine years' schooling for all children, giving them a better chance to enter secondary education.

But special priority should be given to girls, the humanitarian organization said, with greater funding and programs to stop child marriage and violence in schools -- two main reasons for the current dropout rate among girls.

In many cases, poor families pull daughters from school out of fear for their health or safety. In Ghana, 83 percent of parents interviewed for the report said the risks of pregnancy were a disadvantage of school.

The report said that in Togo, 16 percent of children interviewed named a teacher responsible for a classmate's pregnancy. That figure was 15 percent in Mali and 11 percent in Senegal.

In Ghana, 75 percent of children said teachers were the main source of school violence.

The opposite trend is also true, with school attendance leading to an ever-widening series of benefits.

"If adolescent girls stay in school and obtain real skills, research shows that they will earn more income in the future, marry later, and have fewer and healthier children," Plan said. "In the longer term, secondary education protects girls against HIV and AIDS, sexual harassment and human trafficking."

As the report came out, Pakistani teen Malala Yousafzai was fighting for her life after being shot in the head in broad daylight on a school bus.

Her struggle resonated with tens of thousands of girls denied an education by militants across northwest Pakistan, where the government has been fighting local Taliban since 2007.