What is Cesarean Section Scar Endometriosis?
Cesarean section (C-section) scar endometriosis is a unique and distressing form of extra-pelvic disease where endometrial-like tissue implants and grows directly within the surgical incision of a previous C-section. During the delivery of the baby, microscopic endometrial cells from the open uterus can inadvertently escape and become trapped in the layers of the abdominal wall—including the subcutaneous fat, the fascia (the tough connective tissue encasing your muscles), or the rectus abdominis muscles themselves.
Over time, these trapped cells form a dense, inflammatory nodule. Because this condition occurs in the abdominal wall rather than the pelvic cavity, it is incredibly complex and widely misdiagnosed. Patients who report a painful lump near their scar are routinely dismissed by general practitioners who mistake the nodule for a suture granuloma, a lipoma, an incisional hernia, or simply “normal” scar tissue pain. Consequently, women often suffer for years before finding a specialist who recognizes the cyclical, gynecological root cause of their abdominal pain.
The most common symptoms
The symptoms of C-section scar endometriosis are distinct, tactile, and highly mechanical. Because the disease is trapped within the tight layers of the abdominal wall, the inflammation creates severe pressure. The defining feature is the cyclical timing of the symptoms, which escalate directly in tandem with the menstrual cycle.
A Palpable, Swelling Nodule (Lump) in the Scar
The most classic symptom is a distinct, firm lump located directly underneath or immediately adjacent to the C-section scar. For most of the month, the mass may feel like a hard knot of scar tissue. However, in the days leading up to and during your menstrual period, this nodule actively bleeds internally. Because the blood has nowhere to escape, the lump engorges, swells in size, and becomes incredibly firm and prominent.
Cyclical, Burning Abdominal Wall Pain
Patients typically experience severe, localized pain exactly where the nodule is located. Unlike the deep, generalized pelvic cramping associated with standard endometriosis, this is a sharp, burning, or stabbing pain on the surface of the abdomen. During menstruation, the swollen nodule stretches the surrounding muscle and fascia, making the area exquisitely tender to the touch. The pain is often so acute that simply wearing a seatbelt, wearing high-waisted clothing, picking up your child, or engaging your core muscles (like sitting up in bed) becomes agonizing.
Skin Discoloration over the Incision
In some cases, if the endometriotic nodule has grown close to the surface of the skin, you may notice cyclical changes in the color of your C-section scar. The skin directly over the lump may take on a bruised, bluish, purple, or dark brown appearance that darkens during your period as the lesion bleeds beneath the surface. In rare, advanced cases, the scar may even lightly seep or bleed externally during menstruation.
Our Surgical Philosophy and Treatment Approach: Complete Excision and Abdominal Wall Reconstruction
Gold-Standard Nerve-Sparing Excision Surgery
At Endometriosis Surgical Specialists International (ESSI), our approach to C-section scar endometriosis goes far beyond standard gynecological care. We perform wide local excision paired with expert abdominal wall reconstruction.
- We do not believe in draining the nodule or prescribing hormonal suppressants, as neither will cure a dense, fibrotic mass embedded in your muscle. Our high-volume specialists meticulously dissect the entire endometriotic nodule out of the abdominal wall. Crucially, we ensure completely clean, disease-free margins. This means we remove the tumor entirely in one piece without rupturing it, which is the single most important factor in preventing the disease from returning.
Because these nodules frequently grow deep into the fascia and the rectus (core) muscles, removing them creates a structural defect in your abdomen. As experts in complex pelvic and abdominal surgery, our team seamlessly transitions from disease excision to functional repair. We expertly reconstruct the muscle and fascia layers—sometimes utilizing specialized surgical mesh if the defect is large—to restore the strength and integrity of your core. Our goal is to permanently remove your pain while protecting you from future incisional hernias, allowing you to return to a fully active, pain-free life.
C-Section Endometriosis
Frequently Asked Questions
1. Did my obstetrician cause this during my C-section?
It is natural to feel frustrated, but it is important to understand that C-section scar endometriosis is not typically the result of surgical negligence or a “botched” procedure. It is a known, albeit rare, biological risk of the surgery. During a Cesarean delivery, the uterus is opened, and microscopic endometrial cells are exposed to the surgical field. Even with the most meticulous surgical washing and closure techniques, a few of these resilient cells can implant in the abdominal wall and grow over time.
2. Can I just take birth control to shrink the lump instead of having surgery?
No. While hormonal medications (like birth control pills or Lupron) can sometimes temporarily reduce the swelling and lessen the cyclical pain by suppressing your period, they will not shrink or dissolve the physical nodule. C-section scar endometriomas are heavily fibrotic—meaning they are made of dense, tough scar tissue that does not disappear with medication. The moment you stop taking the hormones, the swelling and pain will return. The only definitive cure is the physical, surgical excision of the mass.
3. Will removing the lump from my stomach muscles cause a hernia?
If performed by a general surgeon unfamiliar with the depth of these nodules, there is a risk of weakening the abdominal wall. However, at ESSI, this is precisely why our surgical approach is twofold: excision and reconstruction. When we remove the nodule from your fascia (the connective tissue holding your muscles together), we do not just leave a hole. We perform a specialized fascial closure to tightly repair the defect. If the nodule was exceptionally large, we may reinforce the repair with a surgical mesh to ensure your abdominal wall is entirely secure, specifically designed to prevent hernia formation and preserve your core strength.