Dorries was born as Nadine Vanessa Bargery in Liverpool. Her father was a bus driver who became a lift operator having suffered from Raynaud's disease, which had necessitated the amputation of his toes. Her father was a Roman Catholic of Irish descent, while her mother was an English Protestant. Dorries was raised as a Protestant.

In 2009, she gave this account of her 2005 selection: "Three weeks before the 2005 general election I, a council estate Scouser, was selected as the Conservative candidate to represent a southern rural constituency. Because the vacancy occurred so quickly and so close to D-day, the party provided my association with a shortlist of seventeen candidates, of which about five were women. Following a long day of interviews in hot sunny rooms, the list was whittled down to a shortlist of three ... I was informed that I had been selected outright on the first ballot ... That pride, that sense of achievement, the knowledge that I was selected on the basis of my performance and merit above all other candidates on that day is what enables me to hold my head up high in this place." Dorries's account of her own selection appears to contradict a news report which The Times ran at the time, reporting that Conservative Campaign Headquarters placed a majority of women on the shortlist and pressed for the selection of a female candidate: "Mrs Dorries, who has three teenage children, easily beat her 11 rivals and won the plum safe seat on the first ballot at the selection this weekend. Party officials were thrilled that the seat has gone to a woman. Previously, only two women had been selected in the 17 safe seats where sitting MPs have retired. Senior party figures had made clear to local dignitaries that they would like the seat to go to a woman and presented the constituency with a shortlist of seven women and five men to underline the point." In a debate on Woman's Hour, broadcast on 22 August 2001, Dorries (as Nadine Bargery) had advocated all-women shortlists if the behaviour of Conservative selection committees did not change. In 2009 though, Dorries was highly critical of David Cameron's proposal to consider using all-women shortlists, arguing against a move which would create "two classes of MPs". She wrote that "Sometimes I feel sorry for some of the Labour women who were selected via all-women shortlists. Everyone knows who they are. They are constantly derided." Dorries was elected to the House of Commons at the 2005 general election for the safe seat of Mid-Bedfordshire on the retirement through ill health after a series of scandals of Jonathan Sayeed, with a majority of 11,355, and made her maiden speech on 25 May 2005. She was re-elected in 2010, with an increased majority and a swing of 2.3% from the Lib Dems. Dorries, described as "a right-wing, working-class Conservative", is a member of the socially conservative Cornerstone Group. A Christian, she has said in an interview for a Salvation Army newspaper: "I am not an MP for any reason other than because God wants me to be. There is nothing I did that got me here; it is what God did. There is nothing amazing or special about me, I am just a conduit for God to use." Dorries initially supported the attempt of David Davis to become Conservative leader in 2005 but later withdrew her endorsement. David Cameron, the successful candidate, though "represent[s] everything that through my life . . . [I have] been suspicious of." In May 2007, she criticised Cameron for ignoring the recommendations of the Conservative public policy working group in favour of grammar schools. However, she did defend the selection of Elizabeth Truss in 2009, whose Conservative candidature was called into question after an extra-marital affair was revealed. Dorries served as a member of the Innovation, Universities, Science and Skills Committee. In the year to November 2008, she attended only 2% of sessions. The committee then reformed as the Science and Technology Select Committee; she did not attend a single session. In 2010, she was elected to the Health Select Committee. Dorries has said she witnessed "botched" abortions on two occasions, an experience that influenced her campaign to lower the point during a pregnancy at which an abortion can be performed. On 31 October 2006, Dorries introduced a Private Member's Bill in the House of Commons, which would have reduced the time limit for abortion in Great Britain from 24 to 21 weeks; introduced a ten-day 'cooling-off' period for women wishing to have an abortion, during which time the woman would be required to undergo counselling; and accelerate access to abortion at the end of the cooling-off period. Dorries alleged she had received death threats from pro-choice activists and was given police protection. Parliament voted by 187 to 108 to reject the bill. In May 2008, Dorries tabled an amendment to the proposed Human Fertilisation and Embryology Bill seeking to reduce the upper limit for abortions to 20 weeks from the current 24 weeks of pregnancy. Reportedly written by Andrea Williams then of The Lawyers' Christian Fellowship, Dorries has denied that her campaigning on the abortion issue receives funding from Christian fundamentalist groups, although Dorries website for the "20 Reasons for 20 Weeks" campaign in 2008 was registered by Christian Concern For Our Nation (CCFON), another organisation with which Williams is involved; one of the pressure group's interns set up the website without charge to Dorries. According to Guardian journalist Kira Cochrane it was the greatest challenge to women's abortion rights in nearly 20 years. Dorries' amendment was defeated by 332 votes to 190, with a separate 22-week limit opposed by 304 votes to 233. A majority of MPs continued to support the 24-week limit. She said of her tactics on this issue in 2007: "If I were to argue that all abortions should be banned, the ethical discussions would go round in circles ... My view is that the only way forward is to argue for a reduction in the time limit ... it's every baby's right to have a life."

What was the experience?
Dorries has said she witnessed "botched" abortions on two occasions,