LONDON — A 19-year-old woman who left Britain in 2015 to join the Islamic State and who says she is nine months pregnant has told a reporter that she fled the last remaining village held by the terrorist group in Syria and wanted to return home.

But the woman, Shamima Begum, faces an uncertain future, with no clear answers about how she would get home to east London, or about whether Britain would try to prosecute her for terrorist offenses if she did.

Speaking to a reporter for The Times of London in Al Hawl refugee camp in northeastern Syria, Ms. Begum said she had left the village of Baghuz, the last speck of land under Islamic State control in Iraq and Syria, as Kurdish-led forces allied with the United States closed in. Her Dutch husband, an Islamic State fighter whom she married soon after arriving in Raqqa, Syria, surrendered to Syrian fighters allied to the Kurdish-led forces.

Ms. Begum said that she had lost two children — an 8-month-old son and a daughter who was nearly 2 — to illness and malnutrition in recent months, and that she feared for her unborn child.