Phil Bryant, Mississippi's governor, signed the U.S.' most restrictive abortion rule into law Monday.
The law bans abortions after 15 weeks of pregnancy, even in cases of incest or rape. The only exceptions are for fetuses with health problems that make them "incompatible with life" or pregnancies that might threaten a woman's life.
Bryant has said before he wants to make Mississippi the "safest place in America for an unborn child." The state has one of the highest infant mortality rates in the nation.
Mississippi's only abortion clinic says it plans to sue. The Center for Reproductive Rights and Planned Parenthood say the law is unconstitutional.
