Girls and women 'hit the hardest' by global recession
Girls are "the largest marginalised group in the world", says one the report's authors
Women and girls were hit the hardest by the global recession, according to child rights and development organisations.
"The world is failing girls and women," a report by Plan International and the Overseas Development Institute said.
A shrinking economy sent girls' infant mortality soaring, and more females were abused or starved, they said.
This could erode gains made in recent years towards reaching the Millennium Development Goals, they added.
"The improvements made during the last five years are very fragile," Nigel Chapman, chief executive of child rights organisation Plan International, told BBC News.
"It is shocking, because I don't think anyone's really noticing it."
The problems started when the girls were very young, Mr Chapman explained.
Jorn Madslien Business reporter, BBC News
The report on the impact of the downturn on girls and women was released to coincide with this week's World Economic Forum annual meeting in Davos.
The child rights and development organisations hope to attract the attention of global political and economic leaders, including United Nations Secretary General Ban Ki-moon, who will be there to consider progress towards the Millennium Development Goals.
The eight goals, which cover "halving extreme poverty to halting the spread of HIV/Aids and providing universal primary education, all by the target date of 2015", were initially widely supported by the governments of the 189 countries that adopted the Millennium Declaration in 2000.
This year in Davos there is widespread realisation that time is running out, that in many areas too little has been done, and that with reports of recent setbacks it is time to decide what they are going to do about it.
"Girls are the largest marginalised group in the world," said Mr Chapman, who is also the author of the report.
The proportion of baby girls who died when the economy shrank rose five times faster than the proportion of baby boys who died, he said.
Hence, a 1% fall in economic output increases infant mortality by 7.4 deaths per 1,000 girls against 1.5 for boys, said Mr Chapman, citing World Bank research into previous crisis in 59 countries.
"It's the most stark example of the impact of exacerbated poverty," said Mr Chapman.
More work, less food
The authors of the report, which draws on evidence from a wide range of sources such as academic studies or papers published by the World Bank, points out that there is a lack of data gathered specifically to measure impact based on gender.
"However, from what is available it is clear that girls and young women are at specific risk during periods of economic uncertainty and stress," the report stated.
As the recession caused poverty to spread, older girls were increasingly taken out of school, says the report.
Primary school completion for girls fell 29% whereas for boys it fell 22%.
Many girls were taken out of school to help out at home because their mothers had to work longer hours for less pay, the report found.
"Girls get sucked into domestic chores," said Mr Chapman. "And once they stop going to school it's very hard to get back into the rhythm of things."
In many cases, an increase in the number of child marriages was observed once the downturn hit. "Poverty-struck families simply could not afford to feed those mouths, so they'd marry them off early," said Mr Chapman.
The report warns that the global recession means more girls miss out on school
Others were sent out to work as child labourers - sometimes as sex workers.
At home, girls and women would often eat less to make sure the main "breadwinner" had enough to eat, so the levels of food shortages and malnutrition were more common among girls than boys, with women often making even greater sacrifices for their children.
"They got weaker and less healthy," said Mr Chapman. "They got into a downward spiral."
Meanwhile, girls and women suffered more neglect and abuse than they did before the economic downturn.
Or when pregnant, they received less help than previously, leaving girls between 14 and 19 particularly at risk of death in pregnancy, the report said.
Girls and women also experienced reduced access to basic services and social safety nets, it said.
"Girls' fundamental human rights are increasingly under threat," said fellow author Nicola Jones, research fellow at the Overseas Development Institute.
Much of the problem lies with "entrenched gender inequality", according to Mr Chapman, though current challenges such as austerity budgets and long-term economic trends.
To solve the problem, international programmes must be set up to ensure young women are properly fed, to protect them socially, to make sure they get to go to school and to create jobs for them after they have finished their education, the report recommended.
"We must close the gap between girls and women on the one hand and boys and men on the other," said Mr Chapman.
Inauguration Day: Obama sworn in for second term
Barack Obama has officially been sworn in for his second term as US president in a small ceremony at the White House.
Mr Obama took the oath in the Blue Room to meet the 20 January date set out in the US Constitution.
Given this fell on a Sunday, a public inauguration with pomp and circumstance will take place on Monday.
Vice-President Joe Biden was sworn in for a second term at a small ceremony at his official residence earlier on Sunday morning.
Supreme Court Chief Justice John Roberts administered the oath of office to Mr Obama, witnessed by First Lady Michelle Obama and their daughters Sasha and Malia as well as some family members and reporters.
Resting his hand on a Bible used for many years by his wife's family, Mr Obama vowed "to preserve, protect and defend the Constitution of the United States".
He will repeat those words during Monday's public inauguration, in which he will also set out his plans for the next four years.
Mr Biden will also repeat his oath publicly on Monday.
Bunting and Beyonce
Thousands of workers and volunteers have been working to finish construction for Monday's celebrations, with white tents, trailers and generators being set up along the Washington Mall's parade route as nearby buildings were adorned with red, white and blue bunting.
For his part, Mr Obama rolled up his sleeves and donned gloves to spend Saturday sprucing up a school with other volunteers, as part of a National Day of Service kicking off the inauguration ceremonies - similar to the way he spent the day before his first presidential inauguration in 2009.
He urged volunteers to honour the memory of civil rights leader Martin Luther King, whose birthday, a national holiday, falls on Monday. This year is the 50th anniversary of King's march on Washington.
President Obama's second term work will be more of a challenge than Saturday's school work, says the BBC's Ben Wright in Washington - trying to change America's gun laws, reforming immigration and dealing with the country's debt.
Joe Biden takes the Oath of Office for his second term as Vice-President
In 2009, nearly two million people crammed into Washington to witness President Obama's first inauguration.
Four years on, the mood is unlikely to match that excitement, says our correspondent.
But, he adds, the second inauguration of America's first black president is a moment many will not want to miss.
Hundreds of thousands of people are expected in Washington for that event - a smaller number than the 1.8 million who flocked for the swearing-in in 2009.
They will crowd onto the Mall leading to Congress wrapped up against the cold, to see their president take the oath of office on the steps of the flag-draped Capitol and listen to his speech.
The day will include music from Beyonce and Fun, parades, black tie balls and very tight security.