From the Mayo Clinic website:
Back pain during pregnancy: 7 tips for relief
By Mayo Clinic staff
No. 1: Practice good posture
Stand up straight and tall.
Hold your chest high.
Keep your shoulders back and relaxed.
Don’t lock your knees.
Good posture also means sitting with care. Choose a chair that supports your back, or place a small pillow behind your lower back. Keep your upper back and neck comfortably straight. Consider propping your feet on a low stool.
No. 2: Get the right gear
Wear low-heeled shoes with good arch support. Wear maternity pants with a low, supportive waistband. You might also consider wearing a maternity support belt. Although research on the effectiveness of maternity support belts is limited, some women find the additional support helpful.
No. 3: Lift properly
When lifting a small object, squat down and lift with your legs. Don’t bend at the waist or lift with your back. It’s also important to know your limits. Ask for help if you need it.
No. 4: Sleep on your side
Sleep on your side, not your back. Keep one or both knees bent. It might also help to place one pillow between your knees and another under your abdomen, or use a full-length body pillow.
No. 5: Try heat, cold or massage
Use a heating pad to apply heat to your back, or alternate ice packs with heat. Rubbing your back also might help. Better yet, ask someone to rub your back for you or schedule a professional prenatal massage.
No. 6: Include physical activity in your daily routine
No. 7: Consider complementary therapies
Some research suggests that acupuncture can help relieve back pain during pregnancy. Chiropractic treatment seems to provide comfort for some women as well. If you’re considering a complementary therapy, discuss the options with your health care provider first. He or she may want to confirm that your back pain isn’t caused by an underlying condition.
Know when to consult your health care provider
However common, back pain during pregnancy isn’t something to ignore. Consult your health care provider if your back pain doesn’t respond to the self-care strategies described above. Medication such as acetaminophen (Tylenol, others) isn’t necessarily out of the question, but it’s important to check with your health care provider first.