BBC | 9 May 2008
MPs begin debating the Human Fertilisation and Embryology Bill, an updated version of the current legislation which became law in 1990, this week.
It was drafted because of a feeling the existing law was increasingly out-dated and irrelevant to scientific advances made in the last 20 years.
But several of the key issues are causing bitter divisions of opinion.
Prime Minister Gordon Brown was forced to offer a free vote on three controversial areas in order to avert a rebellion by Catholic MPs.