Supporters of the bill say 20 weeks is more than enough time for a woman to decide if she wants to have an abortion.
The bill's main author, representative Andy Gipson of Braxton, also claimed from the floor that the fetus can feel pain.
"There is very strong scientific evidence and it is frankly uncontrovertibly that the unborn can feel pain. And for that reason, seeing the inhumane nature of these abortions is the reason we need this bill," Gipson said.
The scientific debate over fetal pain is not settled, with some neurologist claiming pain cannot be felt until 24 weeks or later.
The bill does not contain an exemption for victims of rape or incest.
Representative Adrien Wooten says that is a major oversight, especially if the victim is a young girl.
"I am asking you about children. The same thing that you are coming before this body and saying that you are trying to protect. What about those that are walking around that are going through these circumstances that you are refusing to make an exception for in this bill. What about them?" Wooten asked.
An attempt to add a rape and incest exemption to the bill was rejected by the house.
The bill does allow an abortion after twenty weeks if the mother's life is in danger or if there are sever fetal abnormalities.
Of the 21-hundred reported abortions performed in in 20-12, two were occurred after 21 weeks of gestation.
However, another 382 were listed as an unknown gestational age.
Mississippi lone abortion clinic says the bill would not effect them because they do not perform abortions after 16 weeks of pregnancy.