Professor John Crown, who criticised delays in vital clinical drug trials at Dublin's Mater Hospital last week, said he could not see how delaying access to new drugs could be seen as "pro-life."
Prof Crown, who works at St Vincent's University Hospital in Dublin where similar trials were delayed for similar reasons last year, made his comments as the row continued over the delays at the Mater of clinical trials of Tarceva.
The drug was fast-tracked by US health authorities for early testing because it has been shown to increase survival for patients with advanced lung cancer by months.
However, the Mater claims it deferred planned trials on Tarceva because the wording of an information leaflet for the drug ran counter to the hospital's Catholic ethos over its advice that female patients would have to use birth control.
But Prof Crown said drug companies are not forcing people to use contraception.
Roche Pharmaceutical, the company behind the drug, also said there was no such requirement to use contraception and that women could abstain from sex if that was there preferred way not to become pregnant.
Prof Crown also said he was "very anti-abortion" and he criticised people for bringing the abortion issue into this debate.
He also commended two leading Mater-based cancer specialists who spoke out on the trial delays over the weekend.
DEIRDRE, aged 30, a health care professional, was diagnosed with breast cancer 18 months ago. She is undergoing treatment in the Mater Private Hospital.
"When I first went in for chemotherapy, they advised me not to get pregnant - sensible and practical advice.
"If I did get pregnant on chemo, the most likely thing is that I'd have had a miscarriage. If you had a miscarriage on top of everything else you had to deal with at that point, it would be such unnecessary pain and anguish to go through. "Secondly, you might have a baby with serious difficulties, and that in itself again would seem to be an added burden.
"And the third thing, you might have decided to not have any treatment. The likelihood is that one mightn't survive. There are so many necessary things to go through with cancer. The unnecessary things shouldn't be asked of the patient."
Deirdre said the prognosis for people diagnosed with breast cancer has improved vastly over the last decade because of clinical trials.
"The outcomes for patients are very good. Clinical trials are very important," she said. "Time is very important when it comes to cancer treatment. From a patient's point of view, it is important to speed things up and fast-track access to clinical trials."