Washington, DC (LifeNews.com) -- A new survey of doctors nationwide finds 52 percent said they oppose abortion and others wouldn't refer women considering an abortion to a place that does them. The survey also found some physicians believe it is appropriate to withhold information about abortion on moral grounds.

University of Chicago researchers conducted the study with interviews of 1,144 doctors around the country. It is believed to be the first comprehensive survey of the moral attitudes of physicians.

The study found 14 percent of those surveyed do not believe they are required to tell a patient about all treatment options when it comes to morally objectionable procedures such as abortion.

And 29 percent of physicians say they do not feel they must refer someone to another doctor for a treatment they oppose or were undecided.

Doctors who described themselves as strong Christians, whether Protestant or Catholic, were more likely to refuse a referral or more information about morally objectionable procedures like abortion.

Dr. Gary Smith, an obstetrician and gynecologist at the Women's Health Center at Robinwood in Hagerstown, Maryland, is one such doctor.

Smith does not do abortions or refer women to physicians that do and he won't tell a pregnant woman that abortion is an option.

"They know it's an option," he told the Baltimore Sun newspaper. "They don't need me to tell them abortion exists."

"I was always taught I have two patients: the mother and the baby," he said. "Why would I want to send somebody out to hurt their baby?"

Female doctors were more likely to refer women to abortion practitioners than male physicians the study showed.

The survey also found that 42 percent of physicians opposed prescribing birth control to a minor without parental approval.

Dr. Farr Curlin, a University of Chicago ethicist and internist, led the study, which was published in Thursday's New England Journal of Medicine.

Some 1,820 practicing U.S. family doctors and specialists chose randomly from a database were mailed a survey and 63 percent of them responded.