Germany has become the first country to allow parents to leave gender off their baby's birth certificates.

German parents may register their children as neither male nor female if they display characteristics of both genders, the BBC reported. The babies would be in a new category labeled "indeterminate sex."

The decision is part of an effort to avoid parents being forced to make quick decisions regarding gender assignment surgeries on their newborns.

About one in 2,000 people are considered to be "intersex," meaning they have a mixture of female and male chromosomes or genitalia, the BBC reported.

"Some people have life-endangering conditions that require surgery, but most kids do not," New York City psychiatrist Dr. Jack Drescher, who specializes in gender identity, told ABC News. "You can make a gender assignment without surgery, and then see how identity develops. The science of knowing how a child will develop any gender identity is not very accurate. ... Nobody can answer the questions about why this happens. It's like the mystery of why people are gay."

Most doctors use the information they have to assign the best gender to intersex babies.

The law was changed after many people in Germany reported "great unhappiness" from gender-related issues, the BBC reported.

"I am neither a man nor a woman. I will remain the patchwork created by doctors, bruised and scarred," one person in a case said.

Instead of the usual "M" and "F" symbols on passports, Germans will now have the option to be assigned the label "X." Australians and New Zealanders do not legally recognize "gender X" but have allowed it on their passport applications since 2012. South Asia, Bangladesh has recognized an "other" gender category on passport applications since 2011. Nepal has included an intermediate gender on their census since 2007. Pakistan allows an "other" category on identification cards.

The European commission released a report in 2011 that described intersex as ""differ[ent] from trans [sexual or gender] people, as their status is not gender related but instead relates to their biological makeup (genetic, hormonal and physical features), which is neither exclusively male nor exclusively female, but is typical of both at once or not clearly defined as either," ABC News reported.

"These features can manifest themselves in secondary sexual characteristics, such as muscle mass, hair distribution, breasts and stature; primary sexual characteristics such as reproductive organs and genitalia; or in chromosomal structures and hormones," the report stated, according to ABC.