A total of nearly 25,000 procedures have now been cancelled as a result of industrial action during the row.
Junior doctors are expected to stage a fifth strike on April 26 and 27 when they will fully withdraw labour between the hours of 8am and 5pm.
It will be the first time in this country that doctors have staged a full walk-out. In previous strikes junior doctors provided emergency care cover.
Here is a timeline of how the dispute developed:
:: October 12 - Junior doctors demand ‘’concrete assurances’’ from the Health Secretary Jeremy Hunt, saying the ‘’threat’’ that a contract will be imposed upon them must be removed.
:: October 17 - Up to 20,000 people take part in a protest in London over the Government’s plans to impose a new contract for doctors. Under the plans, the contract will reclassify doctors’ normal working week to include Saturdays and late evening working, with critics arguing it could lead to pay cuts of up to 30%.
:: November 4 - Government offers doctors time-and-a-half for night shifts, time-and-a-third for Saturday evenings and Sundays and an 11% pay rise.
:: November 19 - A total of 27,741 doctors (98%) vote in favour of strikes after being balloted by the BMA.
:: November 30 - Strikes planned for December 1, 8 and 16 are called off at the last minute. Government agrees to suspend its threat to impose a new contract.
:: January 4 - BMA announces three strikes in England in January and February when only emergency care will be available. Talks between the union and the Government last less than an hour before breaking down.
:: January 12 - Thousands of doctors walk out for the first strike in 40 years. Around 4,000 operations and procedures are cancelled during the 24-hour walkout.
:: January 13 - Nick Hulme, chief executive of Ipswich Hospital NHS Trust, warns junior doctors’ views are being ‘’skewed’’ by ‘’misinformation’’ about the dispute on social media.
:: January 16 - A new offer from the Government says that, as part of an overall agreement, a premium rate of pay could kick in from 5pm on Saturdays rather than 7pm. Premium pay could start at 9pm Monday to Friday rather than the original offer of 10pm. Dr Johann Malawana, chairman of the BMA’s junior doctor committee, welcomes the involvement of Sir David Dalton but says an agreement could still not be made. Talks remain ongoing.
:: January 18 - David Cameron says the Government has not ruled out imposing a new contract on junior doctors if their dispute over new terms and conditions cannot be resolved in talks.
January 19 - The BMA suspends plans for 48-hour industrial action due to take place on Jan 26, on the basis that some progress is being made in the talks.
:: January 29 - Talks break down between the BMA and the Government. The main sticking points are unsocial hours, how rotas would be staffed and the fact the Government wants to ‘’punish’’ doctors who worked the hardest.
:: January 30 - Family doctor and head of the BMA’s general practice committee, Dr Chaand Nagpaul, warns that GPs are operating in ‘’a state of emergency’’ because of problems with resources and staffing levels.
:: February 1 - The BMA announces a strike will take place the following week on Wednesday February 10.
:: February 2 - Health Secretary sends letter to BMA council chairman, Dr Mark Porter, saying he is ‘’sorry to learn’’ that strike will be going ahead and that his ‘’door is open’’ for negotiations.
:: February 6 - Vanessa Redgrave and Dame Vivienne Westwood join hundreds of protesters for a ‘’masked march’’ through London in protest over pay and conditions.
:: February 7 - The Scottish Government launches a recruitment drive to encourage junior doctors to consider careers in Scotland.
:: February 9 - Government is accused of blocking deal put forward by the BMA that would see junior doctors’ basic pay rise by about half the 11% offered by ministers in return for Saturday not to be treated as a normal working day. Jeremy Hunt refuses to deny claims that he rejected a deal that could have averted further industrial action.
:: February 10 - Thousands of junior doctors all over England take part in the second day of strikes.
:: February 23 - Three 48-hour strikes are announced by junior doctors to take place in March and April.
:: March 9 and 10 - Thousands of operations are cancelled as walkouts take place over two days.
:: March 31 - Details of the new contract are published by the Government on the same day the BMA launches a judicial review challenging the lawfulness of the decision.
:: April 5 and 6 - A second legal challenge is made by NHS staff campaign group Just Health and more strikes are held, causing around 5,100 procedures to be postponed. The cast of Green Wing reunited at the hospital they filmed at to show their support for junior doctors.
:: April 7 - Sir Bruce Keogh, NHS England’s medical director, says the next strike would “irreparably damage” trust in the profession and urges doctors to rethink the move.
:: April 19 - The BMA offer to call off their next strike if Jeremy Hunt removes his threat to impose a new contract. The Health Secretary says it was not possible to “change or delay” the introduction of the controversial contract despite pleas from senior medics.
:: April 21 - Leaked emails suggest an indefinite walk-out is one option that may be on the table.
:: April 22 - A poll of medical students suggests eight out of 10 are more likely to work outside the UK following the dispute over new contracts.
:: April 23 - NHS England confirms that 125,000 operations and appointments have been cancelled because of the upcoming strike and warns that ambulance trusts may need to put on temporary treatment centres.
:: April 23 - A group of cross-party MPs call on Jeremy Hunt to trial the new contract in a small number of trusts hoping the BMA would agree to call of the next strikes if he agreed. A Government spokesman says the contract being phased in was always the plan but there could be no more delays.