Back pain in the third trimester

By trimester

Weeks 28–birth

3rd trimester

This is when the load is heaviest on your body. Support belts, pelvic-floor or prenatal physical therapy, warm heating pads, and a pillow between your knees for side-sleeping are the main things that help. If the pain comes and goes in a rhythmic pattern, it could be contractions, so get it checked instead of assuming it's ordinary back pain.

What does the evidence show for back pain in the third trimester?

• Back pain is one of the most common third-trimester complaints, and supportive shoes, avoiding heavy lifting, side-sleeping with a pillow, and pregnancy-safe exercise can all help manage it. 1
• Regular pregnancy-safe exercise can reduce how often and how badly your lower back hurts. 2
• New back pain that comes with rhythmic contractions could mean labor, so it needs same-day evaluation rather than home back-pain care. 3
• NSAIDs like ibuprofen should be avoided from 20 weeks on, which is why acetaminophen, not ibuprofen, is the standard pain-relief option for third-trimester back pain. 4
• Preterm labor symptoms include contractions every 10 minutes or more often, with six or more in an hour considered not normal, a low dull backache, and a change in vaginal discharge such as leaking fluid or bleeding. 5
• Kidney infection symptoms include fever and chills, pain in the back, side, or groin, frequent and painful urination, and nausea or vomiting. 6

When should I call my provider about back pain in the third trimester?

Back pain that comes and goes in a rhythmic pattern, especially with six or more contractions in an hour or fluid leaking or bleeding from the vagina, needs same-day evaluation since it can signal preterm labor. Back or side pain paired with fever, chills, or painful urination points toward a kidney infection, which is more common in pregnancy and also needs prompt care. Either combination is a reason to call rather than wait out a normal ache. Whatever the pattern, any symptom that feels beyond your usual range is a reason to call: obstetric teams expect these questions and would rather hear early than late.