Along with the other discomforts that accompany pregnancy, over half of all pregnant women experience low back pain during or immediately after pregnancy. For years, these women were told that low back pain was just a part of the experience. Luckily, that is no longer the case. Help is available.

Although help is available, one research study suggests that less than 15 percent of pregnant women are offered an intervention for their low back pain. "You can't just give a pregnant woman with low back pain a sheet of exercises and expect everything to be fixed," says Heidi Prather, DO, a physical medicine and rehabilitation (PM&R) physician at Washington University School of Medicine in St. Louis. "It's like making a Baked Alaska. If you have the ingredients but no instructions, it won't turn out right." PM&R physicians are specialists who diagnose and treat all types of low back pain, including pregnancy-related pain.

The first step to alleviating the pain is to understand the cause. Experts are now trying to classify low back pain during pregnancy related to a specific site or cause. Health care providers try to delineate low back pain due to problems within the spine versus pain due to pelvic and hip dysfunctions. A physician who can recognize these types of low back pain will use that diagnosis to develop a treatment plan that works. Prather advises "Look for somebody who's well-educated in this area and comfortable working with pregnant women." If a woman's obstetrician cannot help, she should consider visiting a PM&R physician.

Most low back pain is the result of a woman's body adjusting to the pregnancy and preparing for labor and delivery. There are stresses on the spine from a growing uterus, added weight and shifts in posture. Abdominal muscles stretch and become less able to stabilize the pelvis. Ligaments become more lax due to hormonal changes allowing joints to become less stable. All of these factors can contribute to the pain.

Prather says some women have "posterior pelvis pain," a discomfort across the buttocks related to weak muscles and loose ligaments. Pain usually starts in the second trimester when women experience a surge of relaxin, the hormone that helps ease various pelvic ligaments. Relaxin levels go up and down during pregnancy, but surge in the second trimester to expand the uterus for a growing baby and later for delivery. Researchers are still debating relaxin's precise role in provoking pain, but some studies confirm a connection between elevated levels of the hormone and increased discomfort.

Once a physician has diagnosed the cause of the low back pain, a treatment plan will be developed. PM&R physicians educate moms-to-be on proper posture and ergonomic changes they can make to ease the stress they are putting on their backs, and may prescribe physical therapy. PM&R physicians can also create individually tailored exercise programs that target key muscles such as abdominals, gluteals and hamstrings. This added strengthening and flexibility can also help alleviate pain.

Unfortunately, low back pain can remain even after the baby is born. "If pain hasn't gone away in six to 12 weeks, things just may not be falling back into place," Dr. Prather says. "Women are often told 'You had a baby, you're supposed to have some discomfort.' But when the symptoms continue, you need to have them checked." Ignoring a potentially serious problem could cause impairment and disability later.