Hollis Johnson/INSIDER The Wall Street Journal reports that a 25-year-old Japanese woman was asked to take a preganancy test before she could board a plane to the US territory Saipan, an island in the Pacific. Hong Kong Express Airways told the Wall Street Journal that the test was in response to "concerns raised by authorities in Saipan," which has become a birth tourism destination. In 2018, more tourists than residents gave birth in the Commonwealth of the Northern Mariana Islands, where Saipan is the largest island and where some pregnant women are traveling to so that their children are eligible for US citizenship.