The world needs to count its girls!

That's the message that President Obama sent earlier this month when he signed the Girls Count Act into law. Congress had previously approved the act by unanimous vote.

There are 220 million children around the world who are uncounted. They were not registered at birth, and they don't have birth certificates.

The law authorizes the U.S. to support programs in developing countries that make it easier for parents to register a daughter at birth and obtain a birth certificate for her.

I had two questions: Why is a birth certificate so important? And what about boys — don't they count, too?

First, let's consider the piece of paper that attests to your date of birth.

A child with no birth certificate might not be able to enroll in school, get a passport, open a bank account or land a job. And a birth certificate can also prove that a child is too young to work or to marry if the country has passed laws setting an age limit.

Yet in the developing world, many parents are unable to get a birth certificate for a newborn. Sometimes it's a matter of access: Papua New Guinea, for example, has only one location to register births for 7 million citizens. And there are other obstacles. In Uzbekistan, parents must pay a fee. Indonesia won't grant a certificate if the parents don't have a marriage certificate.

How do you start to make progress? In developing countries, a health attendant is on hand for about half of all births. Have the attendant record the birth and issue a certificate, suggests Timothy Evans, senior director for health, nutrition and population at the World Bank Group.

So far, I understand the issue. And I figured there must be data proving that girls are disproportionately not registered compared to boys.

But that's not the case. "The under-registration affects boy and girls equally," says Susan Bissell, the chief of UNICEF's child protection section. "There's no gender difference in the data."

Then why not call it the "Girls And Boys Count Act"?

"We get that question all the time," says Melissa Hillebrenner, director of Girl Up, a U.N. Foundation campaign that promotes health, safety, education and leadership for girls. "Of course boys count. But there are so many additional barriers for girls if they don't have this piece of paper."

Jessica Bousquette, policy adviser for child protection at World Vision, agrees: The lack of a birth certificate "magnifies the discrimination girls already face" — in enrolling in school, for example, or in being able to own land.

In addition, the world really doesn't know how girls are faring if millions of girls aren't counted, Hillebrenner points out. There's no definitive information on how many girls are in school, how many are giving birth at a certain age or how many have reported abuse.

Besides, it's not like boys are being ignored. If countries make it easier to register girls, then it'll be easier to register boys, too.

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