Sacrum pain during pregnancy is extremely common and has a clear physical cause: your body releases a hormone that loosens the ligaments holding your pelvis together, and the resulting instability puts stress on the sacroiliac joints where your spine meets your pelvis. The good news is that a combination of targeted exercises, support tools, and small changes to how you move and sleep can make a real difference.
Why Your Sacrum Hurts During Pregnancy
Your body produces a hormone called relaxin throughout pregnancy. Its job is to loosen the muscles, joints, and ligaments of your pelvis so your body can accommodate a growing baby and eventually deliver. But that loosening comes with a cost: your sacroiliac joints, which normally move only 1 to 3 millimeters, become less stable. The surrounding muscles have to work harder to compensate, and the shifting weight of your uterus pulls your center of gravity forward, compounding the strain on your lower back and sacrum.
Relaxin also affects your posture. With a looser pelvis and back, you may unconsciously arch your lower spine or shift your hips in ways that increase pressure on the sacrum. This is why the pain often flares during specific movements: climbing stairs, getting out of a car, rolling over in bed, or standing on one leg.
Exercises That Stabilize the Pelvis
Strengthening the muscles around your pelvis is one of the most effective ways to reduce sacrum pain, because stronger muscles compensate for the ligament laxity that relaxin creates. These exercises are safe throughout pregnancy with one important modification: after the first trimester, avoid lying flat on your back. That position lets your uterus compress a major vein that returns blood to your heart, which can cause dizziness, shortness of breath, or nausea.
Pelvic Tilts
In your second and third trimesters, do these seated or standing. Sit in a chair with your feet flat on the floor and your weight evenly distributed. Exhale, tighten your abdominal muscles, and rotate your pelvis upward (imagine tucking your tailbone under you). Hold for 3 to 5 seconds, then relax. Repeat 10 times. This gently mobilizes the sacrum and activates the deep core muscles that support it.
Cat Stretch on Hands and Knees
Start on all fours with your shoulders over your hands and hips over your knees. Exhale, tighten your abs, and round your spine toward the ceiling while letting your head drop gently toward your chest. Hold for 10 to 15 seconds, then return to a neutral spine. Repeat 10 times. This stretch relieves compression through the entire lower back and sacrum.
Bird Dog
From the same hands-and-knees position, engage your core and slowly extend your right arm and left leg until they’re level with your spine. Hold for 3 to 5 seconds, return to the starting position, then switch sides. Repeat 10 times total. This builds the deep stabilizing muscles on both sides of your pelvis, which directly supports the sacroiliac joints.
Side-Lying Leg Raises
Lie on your left side with your shoulders, hips, and ankles in a straight line. You can place a small pillow under your waist to keep your spine neutral. Slowly raise your right leg to about a 45-degree angle (or whatever feels comfortable), then lower it with control. Do 10 repetitions, then switch sides. This targets the hip muscles that help keep your pelvis level when you walk.
Supported Squats
Stand with feet shoulder-width apart. Bend your knees and push your hips back as if sitting into a chair, keeping your knees behind your toes. Only go as deep as feels comfortable. Return to standing and repeat 10 times. Squats strengthen your glutes and thighs, both of which take load off the sacrum during daily activities.
How to Sleep With Less Sacrum Pain
Nighttime is often the worst for sacrum pain because you spend hours in one position, and rolling over can jolt an unstable joint. The key is keeping your pelvis aligned while you sleep on your side. Place a pillow (or several) between your knees, thighs, and feet so that your upper leg sits level with your pelvis and mirrors the position of your bottom leg. Without this support, your top leg drops forward or backward, rotating your pelvis and pulling on the sacroiliac joint for hours at a time.
A full-length body pillow can simplify this setup. Some people also find that a thin pillow tucked under the side of their waist prevents their spine from sagging into the mattress. The goal is a neutral spine from your neck to your tailbone, with no twisting through the pelvis.
Pelvic Support Belts
A pelvic support belt (sometimes called an SI belt or sacroiliac belt) wraps around your pelvis to compress the joint and partially replace the stability your loosened ligaments no longer provide. The correct placement matters: the belt should sit low around the pelvis, just above the bony prominences on the sides of your upper thighs, not around your waist or belly. Worn too high, it compresses your abdomen without stabilizing the sacroiliac joints.
Many women find the belt most helpful during activities that provoke pain, like walking, standing for long periods, or climbing stairs. Some wear it during all waking hours when pain is at its worst. It works best as one tool alongside exercise, not a substitute for building pelvic stability through movement.
Pelvic Floor Physical Therapy
A pelvic floor physical therapist specializes in the exact problem pregnancy creates: a pelvis under new mechanical stress. Sessions typically involve hands-on assessment of how your pelvis is moving, followed by personalized stretching and mobility exercises. But what makes this different from following an exercise list at home is the individualized guidance on body mechanics, meaning how to get out of bed, pick things up, carry a toddler, or sit at a desk without aggravating the sacrum.
Therapists also use adaptive tools like wedges, braces, and exercise balls, and can help you develop positioning strategies for labor. If your pain is significant enough that basic exercises aren’t cutting it, this is often the most effective next step.
Chiropractic Care During Pregnancy
Some pregnant women seek chiropractic treatment for sacrum pain, and one technique used specifically during pregnancy is the Webster Technique. It was originally designed to address pelvic alignment and reduce tension in the ligaments supporting the uterus. Chiropractors who are trained in prenatal care use gentle, low-force adjustments that account for a pregnant body’s increased joint mobility. If you’re considering this route, look for a practitioner with specific prenatal certification rather than a general chiropractor.
Daily Habits That Reduce Flare-Ups
Small changes to how you move throughout the day can prevent the repeated micro-stresses that make sacrum pain worse. When getting out of bed, roll onto your side first and use your arms to push yourself up rather than twisting through your trunk. When standing from a chair, scoot to the edge and use your legs to stand rather than rocking forward. Avoid standing on one leg, even for something as brief as pulling on pants. Sit down instead.
Stairs are a common trigger. Take them one step at a time (both feet on each step) rather than alternating, and use the handrail. When carrying groceries or a bag, split the weight evenly between both hands. Uneven loads shift your pelvis sideways and strain the sacroiliac joint on one side.
For temporary pain relief, applying heat to the sacrum (a warm compress or heating pad on a low setting for 15 to 20 minutes) can relax the muscles that tighten around an irritated joint. Acetaminophen remains the safest over-the-counter pain reliever during pregnancy, as aspirin and ibuprofen carry documented risks to the fetus. That said, the FDA encourages minimizing its use during pregnancy when possible, so it’s best treated as a short-term option for bad days rather than a daily habit.
When Sacrum Pain May Signal Something Else
Most sacrum pain during pregnancy is musculoskeletal and, while uncomfortable, is not dangerous. But certain symptoms overlap with preterm labor, which requires immediate medical attention. The key differences: musculoskeletal sacrum pain is typically provoked by movement and relieved by rest or position changes. Preterm labor back pain is a constant, dull ache that doesn’t change with position and is often accompanied by regular belly tightening, a feeling of pelvic pressure, mild cramping, vaginal spotting, or a gush or trickle of fluid. If your back pain becomes constant and is paired with any of those symptoms, that’s a different situation entirely from the movement-related sacrum pain described here.