Sen. Lindsey Graham, R-S.C., has proposed a nationwide law prohibiting abortions after 15 weeks of gestation. (J. Scott Applewhite, AP/The Minnesota Star Tribune)

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When U.S. Sen. Lindsey Graham, R-S.C., recently proposed a 15-week federal abortion ban, he suggested that it could provide a reasonable compromise in the national debate over abortion. While Graham may speak of his ban as some form of political compromise, the only thing it actually would compromise is the health care of millions of women.

Here's a real-life example:

One of our pregnant patients opted for early genetic screening at about 12 weeks of gestation, which involved a blood test and ultrasound. The screening showed very abnormal results, and the patient's ultrasound suggested the fetus had a condition incompatible with life. This, understandably, was terribly distressing to the mother. She felt she had to consider terminating the pregnancy.

Rather than terminate based on this information, she chose instead to pursue more definitive testing and get an amniocentesis and fetal MRI. She then conferred with multiple medical specialists who confirmed that her fetus had a rare genetic disease that would still allow for a normal life. Today, that fetus has become a beautiful, happy and healthy child.

It was not until after 16 weeks of gestation that the test results confirmed that a normal life was possible. If a 15-week abortion ban had been in place, there is a good chance the fetus would have been aborted based on the facts the mother had in hand at that time.

The problem with sweeping abortion bans such as Graham's is that every pregnancy is different. A broad-brush, political solution does not accommodate the wide variety of real-life situations. A fetal anatomy ultrasound, which can show serious birth defects, doesn't take place until 20 weeks — five weeks after the proposed ban's limit. Before this time frame, structures like the brain and heart are too small or underdeveloped to definitively analyze.

Genetic testing, for those who choose it, usually occurs around 12 weeks. At this stage, the testing involves a blood test and possibly an ultrasound. The genetic test primarily looks for major chromosomal anomalies. However, there is no early test for the countless other rare birth defects that may be incompatible with life.

Even if a birth defect appears before the 20-week anatomy ultrasound, we cannot draw any definitive conclusion without further testing. Often, a second ultrasound is necessary to confirm the defect or to check on its progression. Or, in cases like that of the patient we described, further testing could require more advanced diagnostic testing such as an amniocentesis or fetal MRI. Each of these tests can take weeks to schedule, conduct, produce results and analyze.

Patients also require sufficient time to weigh their options. We know from experience that when someone learns of a possible fetal abnormality that may be incompatible with life, the decision about what path to follow is far from instantaneous or straightforward.

Additionally, our health care system unfortunately has only a limited number of facilities and health professionals able to conduct and interpret the required tests. Despite our best efforts to expedite care, it can take several weeks to schedule and deliver it.

Often it's not a single health care professional who does the analysis. Instead, an interdisciplinary team convenes to consider the results and possible outcomes. Many hospitals also have separate ethics boards that can delay treatment when terminating a pregnancy becomes necessary. Each of these steps takes time, and they collectively push well past a 15-week barrier. You simply can't legislate for every possibility or every pregnancy.

While abortion rules under Roe v. Wade may not have been perfect, in states such as Illinois they provided enough flexibility to treat various patients with their individual needs and concerns in mind. An inflexible 15-week abortion ban does nothing of the kind. It will sentence many women to carry babies to term that will not survive birth. It will compel women to terminate pregnancies in which abnormalities are suggested but not verified. It will tie the hands of doctors who strive to provide the best advice and care for their patients. Patients will not have sufficient time to make some of the most painful and personal decisions of their lives.

A 15-week abortion ban may solve a political problem, but it will further complicate the lives of millions of women — including those of us who have devoted our lives to caring for them and their babies.

Dr. Elizabeth Weldon practices obstetrics and gynecology in Downers Grove, Illinois. Dr. Matangi Bala is an anesthesiologist in the Chicago area. This article was first published by the Chicago Tribune.