Back Problems in Pregnancy

Ask women about their most common health complaints during pregnancy, and chances are they'll talk about morning sickness, tender breasts, constipation and fatigue. And for 50 to 70 percent of pregnant women, back pain is just as unwelcoming and frustrating.

The dull, persistent aches--generally in the lower back--tend to strike younger women, those who have had multiple pregnancies, weak backs or pain before pregnancy. And, contrary to popular thought, there doesn't seem to be a connection between the amount of weight gained during pregnancy and an increased risk of back pain.

There is some good news: Unless a woman had chronic backaches before pregnancy, back pain doesn't typically last throughout the entire term. It usually develops between the fifth and seventh month and gradually eases before delivery.

Most women have pain in the sacroiliac joint, the area where the pelvis attaches to the low back. The pain generally makes women feel stiff in the morning and then progresses to soreness.

Many theories exist to explain why pregnant women have aching backs. One thought is that hormonal changes cause ligaments of the back and pelvis to soften, resulting in added stress to those areas and strain to muscles. Carrying 20 or 30 pounds of baby, water and placenta--and an enlarging uterus--only makes matters worse.

A pregnant woman's center of gravity shifts forward under the baby's weight. She usually arches her back to accommodate the extra weight. But this stresses the facet joints and discs, and makes them sensitive--causing pain.

Ironically, as the baby grows, the pain dissipates. Early in the third trimester, the baby changes position and no longer presses on the pelvis--giving women some relief.

A common companion to low backache in pregnancy is sciatica--pain and sometimes numbness that radiates along the sciatic nerve that extends from the pelvis to the lower leg. Sciatica often is caused by increased fluid retention around the muscles and pelvic pressure on the nerve.

In most instances, physicians don't need to order tests to determine the cause of back pain during pregnancy. In rare cases, however, low-back pain may signal more serious problems such as the separation of the placenta or kidney stones or infection. A patient history, examination and sonogram may confirm the diagnosis.

Most obstetricians recommend conservative treatment for gestational back pain. Women can modify their activities, apply heat or ice or take Tylenol. As in any pregnancy, narcotics, muscle relaxants and aspirin should be avoided.

To help prevent a recurrence:

Use correct posture with shoulders, back and buttocks tucked in to help relieve strain on lower back.
Perform mild exercises (pelvic rocking and tailor sitting) to help maintain your back's strength and stamina.
Do not wear high-heeled shoes (higher than 1"), which place added pressure on the back.
Take frequent breaks from activities that require prolonged sitting or standing.
Take a warm bath.
Have a massage.
Consult your physician before using a heating pad.
Sleep on a firm mattress.
Always bend from the knees to lift objects rather than bending at the waist; pull object close to your body and then use your thigh muscles to lift to a standing position.
Talk to your doctor /midwife about using a maternity support belt to lift the abdomen and provide back support.

For information about obstetrics at West Penn Allegheny Health System:

AGH Women's Health

WPH Women's Health

WPH-Forbes Campus Women's Health

Last Updated: February 26, 2009