Pregnancy changes a woman's body in different ways, including the muscles, ligaments, bones, and joints that make up the musculoskeletal system. According to a new literature review in the September issue of the Journal of the American Academy of Orthopaedic Surgeons (JAAOS), hormonal changes during pregnancy can cause many joints to flex beyond normal limits (hypermobility) due to ligament laxity ("loose ligaments"), weight gain, and a shift in the woman's center of gravity. The impact on the spine can accentuate low back curvature and thrust and tilt the pelvis forward, causing pain.
Lumbopelvic—low back and/or pelvic girdle—pain is a common medical condition associated with pregnancy; nearly half of pregnant women experience it. "As ligaments—which connect bones to each other—stretch and the uterus expands as the baby grows, they put excessive stress on the spine and pelvis. This can lead to low back pain, pelvic girdle pain, or both," says author Zbigniew Gugala, MD, PhD.
"Low back/pelvic girdle pain is especially common in pregnant women who are older, overweight, or have a history of back pain during a previous pregnancy. Women who already have joint hypermobility or are bearing more than one child at a time are also at higher risk," says Dr. Gugala. To date, the correlation between lumbopelvic pain and maternal weight gain during pregnancy or birth height or weight of the newborn has not been established.
Pain typically begins at the 18th week of pregnancy and ends between the 24th and 36th weeks of pregnancy. But for many women, delivery doesn't mean the end of back pain.
"About half of women with low back pain during pregnancy continue to experience pain after delivery, sometimes for up to a year," says Dr. Gugala.
Pain management during pregnancy is usually focused on conservative treatments. "Physical exercises before and during pregnancy can be effective in preventing or reducing low back and pelvic pain. But before beginning any exercise regimen, the expectant mother should check with her doctor," says Dr. Gugala.
"Usually, low back and pelvic pain during pregnancy are managed by obstetricians. Depending on the situation and with consideration for the fetus, an orthopaedic surgeon and the obstetrician may develop a combined plan of care regarding labor and delivery. Surgical interventions are not usually indicated unless the pain is due to trauma, such as a fall or some other condition," says orthopaedic surgeon and coauthor Ronald W. Lindsey, MD.
"It is important for the patient and the physician to be aware of the effects of hormones on ligaments and tendons so they can recognize pain symptoms that are outside those considered normal for pregnancy. Some conditions can have lasting, debilitating consequences," adds Dr. Gugala.
Help reduce pregnancy low back and pelvic girdle pains with:
Pregnant women with lumbopelvic pain should be provided with adequate information on low back pain and how to avoid it. This includes how to achieve correct posture, how to practice relaxation techniques, and how to turn in bed. They should also be told to avoid sudden vigorous movements that may lead to extreme joint stretching in the spine and/or pelvis.
Pregnant women should remain active by continuing normal daily activities and work, if possible. Daily routines should incorporate supervised flexibility, stretching, and muscle-strengthening exercises (e.g., aerobics, aquatic training, yoga, and reiki). Various complementary or alternative medicine treatments (e.g., thermal compresses, abdominal belts, massage, acupuncture, and aromatherapy) may be helpful for some women; however, women should always discuss these with their primary physicians and/or obstetrician/gynecologists.