The number of women and girls in the United States at risk of female genital mutilation has more than doubled since 2000 to 500,000.
That is according to demographic researchers, who expect that figure to rise even further.
The report was released on International Day of Zero Tolerance for Female Genital Mutilation (FGM) today.
There is a dedicated clinic in Ireland for those affected by FGM which has treated less than a dozen women since it opened in May 2014.
Most of the women it treated have required surgical intervention.
Read "Cutting culture - A Kenyan revolution" by RTÉ's Gavin Jennings here.
Today's report said the main cause of the rapid growth was a doubling of immigration to the US between 2000 and 2013 from African countries, where the brutal tradition is prevalent.
"We put out these numbers so decisions can be made by policymakers in this country," said Charlotte Feldman-Jacobs, who is an author of the report and director of the gender programme at the non-profit Population Reference Bureau (PRB).
"In order to know where these girls and women are and how many, this data is critical," Ms Feldman-Jacobs added.
FGM, which involves the partial or complete removal of the external genitalia, is considered a necessary pre-marriage ritual for girls in many countries.
However, it can cause lasting physical and psychological damage and even death.
The practice is most common in Africa and the Middle East, though most African countries where FGM is found have banned the practice.
The practice is most common in Africa and the Middle East, though most African countries where FGM is found have banned the practice.
About 55% of the 506,795 women and girls in the US at risk of FGM in 2013 were either born in Egypt, Ethiopia or Somalia, or born to parents from those countries, the researchers found.
Other women and girls in the US at risk of FGM were from or had familial ties to Nigeria, Liberia, Sierra Leone, Sudan, Kenya, Eritrea and Guinea.
"We applied country prevalence rates to the number of US women and girls with ties to those countries to estimate risk," said Mark Mather, a demographer at PRB who co-authored the report.
Overall, about 97% of US women and girls at risk of FGM were from or had ties to African countries, while 3% were from Asia.
