IMPORTANCE Federal policy changes in 2002 and 2009 led some states to expand public health insurance coverage to non-US-born children and pregnant women who are lawful permanent residents during their first 5 years of residency in the United States. In other states, there were concerns that insurance expansion could attract immigrants to relocate to gain free health insurance coverage. OBJECTIVE To examine whether expansion of public health insurance to non-US-born, lawful permanent resident children and pregnant women during their first 5 years of residency is associated with increased interstate migration among these groups.
