More girls in America are having their genitalia mutilated as immigration increases the vibrant diversity of U.S. neighborhoods, says a new report by a D.C.-based nonprofit.

In 2013, “there were up to 507,000 U.S. women and girls who had undergone [genital mutilation] or were at risk of the procedure… the rapid increase in women and girls at risk reflects an increase in immigration to the United States,” said the Friday report by the Population Reference Bureau.

“We’re seeing a lot more F.G.M.,” Dr. Gretchen Heinrichs, a gynecologist, told The New York Times. FGM stands for female genital mutilation.

The new report, titled “Women and Girls at Risk of Female Genital Mutilation/Cutting in the United States,” did not specify how many girls in America aged 15 to 19 are now at risk from the culturally diverse practice, which is generally directed by their immigrant parents.

The practice continues because of pressure from the men and women in the extended families who arrange the eventual marriage of the young women and men. This is seen as vital to the survival of family groups in chaotic, conflict-ridden cultures.

The genital cutting reduces or eliminates women’s ability to achieve sexual pleasure, but gives elders more control over who marries whom. Other cultural practices, including the wearing of hijab headscarves and the promotion of cousin marriage, reinforce the control of young people by their clan or extended family.

Mutilation was not practiced in pre-modern Western Europe, where young men and women were normally expected to choose each other and to marry outside their clans and extended families.

The ancient non-European practice is increasingly being detected in the United States and Europe when immigrant women and the Western-born daughters of immigrants visit taxpayer-funded medical facilities to treat the health problems caused by the vibrantly diverse traditions.

President George W. Bush and President Barack Obama have sharply increased the inflow of women from countries that practice genital mutilation, up from from 228,000 in 2000 to 507,000 in 2013, according to the new report.

Between 2000 and 2013, the African immigrant population in the United States more than doubled, from 881,000 to 1.8 million, said the new report.

The practice is normal among the Muslim populations in northern and eastern Africa, such as Egypt, Sudan, Eritrea, Ethiopia, Kenya and Somalia. It is also very common among the Muslim population of Kurdistan in Iraq and in the fast-growing population of Yemen, adjacent to Saudi Arabia.

The practice is also commonplace among Christian populations in Ethiopia, Eritrea and Nigeria, but the more extreme version occurs in Muslim communities.

Muslim advocates in the United States usually deny that the problem is associated with Islam.

But the procedure is also backed by Muslim immigrants and advocates in the United States. In 2012, for example, a Muslim doctor at the Mayo Clinic promoted the practice as an “honor” for women in Muslim communities. The doctor, who was also a senior member of the Association of Muslim Jurists of America, was subsequently fired by his American supervisors.

Obama’s administration is trying to raise the flow of immigrants into the United States. For example, Obama has decided to import thousands of Syrians among the 70,000 refugees sought in 2015.

However, in a nod to its feminist supporters, the administration is also denouncing the diverse practice.

But the White House’s criticism doesn’t mention the role of immigration or Islam, and is focused on victims in Africa and Arabia, not the increasing number of victims in America.

“Today marks the twelfth annual International Day of Zero Tolerance for Female Genital Mutilation/Cutting (FGM/C),” said a White House statement. “On this occasion, we stand in solidarity with the more than 125 million women and girls alive today who have undergone FGM/C, and we renew the call to end this harmful practice. As the President stated this past summer, FGM/C is a practice that should be eliminated.”

Democrats and progressives favor increased diversity, in part, because the inflow of immigrants and the resulting social conflict helps them transform Americans’ anti-government culture.

Follow Neil on Twitter