Labour's Diana Johnson introduced a ten minute rule bill to decriminalise abortion this afternoon.
She says current legislation, which contains criminal sanctions for both women and doctors if they do not meet certain requirements, is out of date.
Johnson proposes amendments to sections 58 and 59 of the Offences Against the Person Act 1861 which would decriminalise consensual abortions.
She says the amendment would not remove the 24-week gestation limit or deregulate abortions but would allow professional medical bodies to oversee the practice.
But Dr Peter Saunders, chief executive of the Christian Medical Fellowship, told Premier News Hour that decriminalising abortion would completely liberalise abortion.
"We know that the [current law] is widely flouted, to the situation now that we have 200,000 abortions a year and one in every 5 pregnancies end in abortion... This decriminalisation she's talking about would make things much worse than they are at the moment."
Dr Saunders added that the decriminalisation of abortion could lead to changes in how the procedure is carried out.
"It would mean abortion could be performed on any grounds at all up until 24 weeks, it would mean there would be no restrictions on where abortions could be performed, there wouldn't be a requirement for two doctors to agree.
"It would put Britain in a position where they would have abortion laws very similar to those in China and Vietnam amongst the most liberal in the whole world so people are right to oppose this."
There'll be more debate on issue after MPs voted in favour of the idea.
The legislation received 172 votes in the Commons against 142, and will now go to a Second Reading next Friday.
Listen to Alex Williams speaking to Dr Peter Saunders here: