Sacroiliac Joint Pain After Delivery

Written by Bodyful Physical Therapy and Wellness

Postpartum Sacrum Pain and SI Joint Pain After Delivery

Many new mothers and parents experience pelvic discomfort and pelvic pain after childbirth. One of the most common—and often misunderstood—sources of pain is sacroiliac (SI) joint pain postpartum.

In this blog, you’ll learn why SI joint pain occurs after delivery, how it relates to pelvic floor and core function, and how a somatic approach to postpartum physical therapy can support healing.

You’ll also learn three ways you can begin changing your SI joint pain today.

Postpartum individuals experiencing pelvic and low back pain do not have to suffer or simply “put up” with it. There are solutions.

What Is Sacroiliac (SI) Joint Pain?

When new birthing parents describe postpartum back pain, they often assume it’s coming from the lumbar spine. However, when they point to the painful area, it’s frequently lower than the low back, closer to the pelvis.

This often-overlooked joint is the sacroiliac joint (SIJ).

The SI joint is formed where the sacrum (the wedge-shaped bone at the base of the spine) meets the ilium (pelvic bone). Dysfunction here is classified as pelvic pain, not simply back pain. This distinction matters because how we assess and treat pelvic pain differs from how we treat spinal pain.

The SI joint plays a key role in:

• Load transfer between the legs and the spine

• Stability of the pelvis

• Coordinated movement between the core and lower body

Symptoms of SI Joint Pain Postpartum

With SI joint pain after delivery, symptoms may include:

• Localized pain near the sacrum or tailbone

• Pain in the hips or deep buttocks

• Pain that radiates into the thigh or inner leg

• Pain with walking, standing, rolling in bed, or standing on one leg

This type of postpartum sacrum pain may feel movement related, deep, or achy—and can fluctuate depending on activity and fatigue.

Why Childbirth Contributes to SI Joint Pain

Contrary to popular belief, postpartum SI joint pain is often less about instability and more about sensitization and coordination.

Nervous System Sensitization

During pregnancy, your nervous system prioritizes protecting the pelvis. Research shows the body increases sensory and pain-receptive nerve fibers in this region to heighten awareness and protection.

This is adaptive—but when combined with inflammation, physical strain, sleep deprivation, and emotional stress, it can contribute to persistent postpartum pain.

The good news: with time, appropriate movement, and a nervous-system-informed postpartum PT approach, these pain patterns are changeable.

Postural and Mechanical Changes

Pregnancy shifts your center of gravity. These changes affect:

• Foot loading

• Hip strength

• Core coordination

• Abdominal pressure management

If these adaptations persist postpartum without recalibration, they can lead to inefficient load transfer through the SI joint and ongoing symptoms.

Delivery-Related Strain

Both vaginal and cesarean births can influence SI joint pain postpartum.

• Vaginal delivery (especially with assistance or tearing) can lead to pelvic floor tightness or scar tissue. Pelvic floor muscles attach directly to the sacrum and can limit SI joint mobility and blood flow.

• Cesarean birth involves abdominal wall incision and scar tissue. Restricted fascial movement can impair core coordination and increase load through the SI joint.

Diastasis Rectus Abdominis Symptoms and SI Joint Pain

Diastasis rectus abdominis (DRA) is a normal adaptation during pregnancy. However, if abdominal coordination and strength do not recover postpartum, abdominal pressure management may become inefficient.

This can sensitize the SI joint and contribute to ongoing pain. Common diastasis rectus abdominis symptoms include:

• Abdominal doming or bulging

• Core weakness

• Back or pelvic pain

• Difficulty transferring load

• Urinary or fecal incontinence

• Pelvic organ prolapse

• Constipation

This is where postpartum physical therapy can be especially helpful.

You Don’t Have to “Just Deal With It”

You may be told that SI joint pain, pelvic pain, or core weakness is “normal” postpartum. Normal does not mean inevitable or untreatable.

The body is resilient. And the first 3–6 months postpartum is an important window for recovery. Individualized postpartum PT can make a meaningful difference in how efficiently and completely you heal.

Bodyful’s Somatic Approach to Postpartum SI Joint Pain

At Bodyful, we combine:

• Skilled manual therapy

• Evidence-based exercise

• Somatic, trauma-informed care

to support faster and more sustainable outcomes.

Core System Assessment

Your core is more than your “six-pack.” It includes:

• The respiratory diaphragm

• The pelvic floor diaphragm

• The transverse abdominis, internal oblique muscles, scapular muscles that connect to the spine and ribs, and multifidi

We assess breathing patterns and diaphragm fascia because restrictions here affect pelvic floor coordination and SI joint loading.

Pelvic Floor Therapy

Pelvic floor tension, weakness, or poor coordination can directly contribute to SI joint pain postpartum.

You can learn more about pelvic floor therapy and internal assessments here.

Dynamic Posture Support

We use developmental kinesiology approaches to retrain abdominal pressure management and spinal elongation. This approach leverages developmental movement patterns to restore efficient movement control—supporting both SI joint and diastasis recti recovery.

Gluteal Coordination

Prolonged sitting can inhibit glute activation (“dead butt syndrome”). Even strong glutes may lack coordination.

We use a research-based gluteal activation exercises shown to improve neuromuscular firing and reduce compensatory strain on the SI joint.

Functional Integration

Strength alone isn’t enough. We integrate all training into real-life movements so your nervous system learns how to apply coordination across multiple planes of motion.

3 Ways to Start Changing SI Joint Pain Today

1. Mindful Movement

Notice if you hold your breath when bending or lifting. Pause, place your hands on your ribs, and breathe 1–3 cycles before moving. Observe how your body responds.

2. Add Band Resistance

Using a resistance band around your thighs during glute exercises—or even while walking—can increase glute activation and change SI joint loading patterns.

3. Optimize Sleep Position

Side-lying with pillows between the knees and under the waist can reduce prolonged strain on the SI joint. Small changes here can create noticeable differences.

Pelvic Health Specialist, Dr. Maryssa

When to Seek Postpartum Physical Therapy

If your pain:

• Persists beyond 3 months

• Worsens over time

• Affects daily function or quality of life

…it’s time to seek care.

A skilled pelvic floor physical therapist has specialized training in the pelvic girdle, pelvic floor, and core coordination. Even if you’ve tried PT before, a pelvic-focused postpartum assessment may offer new insights.

Once postpartum—always postpartum.

Support Is Available

Ready to begin healing your postpartum sacrum or SI joint pain?

You can book a free discovery call to speak directly with one of our pelvic floor PTs and explore whether postpartum PT is right for you.

Do you also experience pain with sex postpartum? Pelvic floor physical therapy can help. Read more here.

Bodyful Physical Therapy and Wellness is located in Oakland, CA, serving the Bay Area in person and offering online postpartum physical therapy for those who cannot attend in person.