Brazilian police can’t explain how Tejano pop diva Gloria Trevi was able to get pregnant, since she has been incarcerated for 18 months in a jail where men and women are held separately, according to Reuters. Police said last month Trevi — who had been compared to Madonna but now is known as Mexico’s fallen queen of pop — may have artificially inseminated herself in hopes that a pregnancy would help her avoid extradition from Brazil, where she has been jailed since January 2000 on charges of sexual abuse. In the past, Brazilian laws have allowed a suspect to avoid extradition if she had a Brazilian child. But Trevi still may not be allowed to stay, especially since officials don’t know the father’s identity. “The conclusion is that it is a mystery that only she can clear up,” Brazilian federal police official Francisco Assis Guimaraes told reporters. He said when Trevi was asked if her “pregnancy had been consensual,” the star had said no. When asked if there had been any violence against her and who the father of the child was, however, she exercised her right not to answer in full and did not respond. Police questioned another inmate and found that he and Trevi’s manager, Sergio Andrade, who is also being held, had given Trevi sperm, which she could have used to artificially inseminate herself. Trevi and backup singer Maria Raquenel Portillo were arrested in Rio de Janeiro on charges they lured young girls to their hotel with the promise of stardom, but then turned them into sex slaves for Andrade, according to Reuters.