Roe v. Wade gave women a right to choose abortion. But doctors like me have a choice, too.

There came a time in medical school when I first witnessed an abortion, a dilation and curettage, where the cervix was dilated and the tiny fetus sucked out by vacuum. The first time I saw the body parts was the first time I knew I would never perform one of these procedures. I was defining my role as a doctor in terms of relieving suffering and extending life, not ending it.

Dr. Ben Carson, consummate pediatric neurosurgeon and current secretary of the U.S. Department of Housing and Urban Development, has come out vehemently against abortion. In an interview in 2015 when he was running for president, he told me, "I've spent many, many a day and many a night operating on premature babies and then seeing them as adults, as productive adults. There is no way that anybody's going to convince me that that's a meaningless mass of cells."

States are challenging Roe v. Wade

I agree completely with Dr. Carson from the point of view of a physician, which is not to say that I have a fixed view on abortion; I don’t. I am sensitive to the devastating impact of rape and abuse on women and the pressure to abort when the mother's life is at risk. I am very aware of the fact that since 1973, Roe v. Wade set a precedent where abortion is legal across the country up to the point of viability, when the fetus can exist on its own outside the womb, which with the help of modern technology is generally considered to be 22 to 24 weeks gestation.

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From a purely public health perspective, Roe makes sense to me. Before Roe, it never made much sense in terms of medical safety for a pregnant woman to be rushing across state lines to an unknown facility in the middle of the night to gain access to a state where abortion was legal.

But Roe v. Wade is currently being challenged with new laws in the states, and the number of states with pending highly restrictive abortion laws is growing. On Friday, Missouri's legislature passed a bill to outlaw almost all abortions after eight weeks. This came on the heels of Alabama Gov. Kay Ivey signing into law a near-total abortion ban law in her state.

Georgia, Kentucky, Missouri, Mississippi and Ohio have all approved bans on abortion once a fetal heartbeat is detected, usually around the sixth week of a woman’s pregnancy. Iowa and North Dakota also approved severe restrictions, which were later struck down in court. None of these laws are yet in effect, but they could lead to a U.S. Supreme Court challenge.

When does life begin?

The current battle over Roe brings up the central question of when life begins. Christians generally say it is at the point of conception, but for Jews, the fetus remains part of the mother’s body, and life generally begins at birth. For Muslims it often seems to be around four months, when the soul enters the body.

As a physician, I am very interested in the notion of life beginning when the heart starts beating, since I pronounce someone dead when their heart stops. But this is not a perfect parallel, since brain function is not the same before birth and upon death, and though the brain’s starting and stopping also guides doctors’ life and death pronouncements, it is not entirely knowable.

I wonder why it seems to be always assumed that we doctors will perform abortions without ever asking us. If Roe establishes a woman’s right to choose, what about the right of the physician who is expected to perform the procedure?

As a practicing physician, I am especially concerned that abortion is too often performed casually or frivolously, or as a backup form of birth control.

Doctors are in the middle of the controversy

People across the country and people of different faiths have very different beliefs regarding pregnancy and abortion. Roe v. Wade established a standard of fetus viability that several states are now trying to undermine, either by attempting to shorten the length of time for a legal abortion to before viability, as in Missouri, or extending legal abortion into the third trimester, as in New York.

I don’t believe this is the best way to carry on a debate. Doctors and judges stand smack in the middle of this controversy.

It is important to remember that as a doctor I am not there to simply carry out the will of the state or the will of the individual, but to do what I see as most in keeping with my medical role. I am not against abortion, but I would rarely perform one. My position needs to be respected, too.

Marc Siegel, a member of USA TODAY's Board of Contributors and a Fox News medical correspondent, is a clinical professor of medicine and medical director of Doctor Radio at NYU Langone Medical Center. Follow him on Twitter: @DrMarcSiegel.

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This article originally appeared on USA TODAY: Roe v. Wade gave women a right to choose abortion. But doctors like me have a choice, too.