Within 20 years, more babies will be born to Muslim women than to Christian women world-wide, the latest sign of the rapid growth that could make Islam the world’s largest religion by the end of the century.

Islam is already the world’s fastest-growing religion, according to a new study released Wednesday by the nonpartisan Pew Research Center, with the Muslim population increasing by more than 150 million people between 2010 and 2015, to 1.8 billion.

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