Bob and Jenny Stokes died at a Swiss clinic
More than half of doctors have been approached by a patient seeking medical help to die, an internet survey suggests.
However, most (74%) would refuse to perform assisted suicide if it were legalised.
The poll of 986 physicians found that only a quarter agreed with giving medical help to die.
A majority (56%) also considered it impossible to set safe bounds to euthanasia.
The poll was carried out by Doctors.net.co.uk and commissioned by the pro-life campaign group Right To Life.
It was released in the run-up to the second reading in the House of Lords of the Patient (Assisted Dying) Bill.
At a news conference in the House of Commons, Chairman of the All-Party Parliamentary Pro-Life Group, Jim Dobbin MP, said: "We welcome these initial results.
"They have provided a wealth of information and demonstrate that a clear majority of doctors are opposed to the Lord Joffe Bill - The Patient (Assisted Dying) Bill - which aims to legalise assisted suicide and is to have its Second Reading in the House of Lords in June."
However, Tamora Langley of the Voluntary Euthanasia Society said other surveys have found most doctors are in favour of assisted suicide.
"The large majority of surveys show a slim majority of doctors are in favour of a patient's right to choose to ask for medical help to die if they have a terminal illness," she told BBC News Online.
She said legislation such as the Lord Joffe Bill contains an opt-out clause for doctors who are opposed to assisted suicide on a matter of conscience.
"Doctors will have a choice too," she said.
The report follows the death in January of 74-year-old Reginald Crew from Liverpool who travelled to Switzerland for help to die.
In April, a British couple, Robert and Jennifer Stokes, died at a Swiss clinic, following an apparent suicide pact.
Helping someone to die is punishable by 14 years in prison under British law.
Current British Medical Association policy is against legalisation of euthanasia and assisted suicide.