The cesarean apron: description, proposed pathophysiology, classification, and prevention through scarpa fascia closure at cesarean delivery

Abstract

The “cesarean apron” is a common, often overlooked post-cesarean contour deformity of skin and adipose tissue which protrudes above or below the cesarean scar. We present new insights into its pathogenesis, a clinical classification based on its severity, and specific treatment recommendations for each level of deformity, with a particular focus on the often -overlooked role of Scarpa fascia closure during cesarean delivery. Given its significant implications, we recommend routine Scarpa fascia closure.

INTRODUCTION:

The “cesarean apron” (also called cesarean bulge, pouch, shelf, or shaft) is a common post-operative contour deformity of the lower abdominal wall characterized by redundant skin and adipose tissue located above the cesarean delivery scar (Figure 1 A, B). It occurs in obese, but also in non-obese women. The deformity typically develops gradually after surgery and is often described by patients as a bulge that sometimes causes physical discomfort, but importantly aesthetic and psychological distress which alters the patient’s self-esteem with feelings of embarrassment or frustration. In most cases, the deformity occurs after an uncomplicated cesarean procedure, and patients have been often advised to lose weight or engage in exercise with the hope that the deformity will disappear with time. The condition is well recognized in social media patient discussion groups, which report stories and share advice on how to deal with it (1–5).

Figure 1.

The Cesarean Apron. A. Frontal view. B. Oblique view. C. Frontal view. D. Lateral view.

The treatment of the cesarean apron often becomes the domain of plastic surgeons who perform abdominoplasties to address the defect. Here, we propose that the cesarean apron is caused by lack of or incomplete closure of the Scarpa fascia, propose a pathophysiologic sequence, classification, and how closure of the Scarpa fascia can be key to the prevention of this deformity.

Early cesarean surgical techniques (Pfannenstiel; Munroe-Kerr) focused on closing fascia and skin, and superficial adipose tissue reapproximation was not listed as a routine step, which probably meant that it was not performed unless there was a particular reason (6–7). In the mid-twentieth century, a surgical principle was that “neither fat nor muscle tolerate suturing well,” and many surgeons avoided placing sutures in adipose tissue unless there was a thick layer with obvious dead space. This longstanding view appears in classic wound-closure manuals (8). Experimental work in general surgery reported in the 1970s warned that closing dead space with sutures could increase the risk of infection, reinforcing the habit of not suturing adipose tissue (9). This practice was absorbed into obstetrical surgery. By the late 1980s and early 1990s, obstetrical practice varied; many obstetricians left the subcutaneous tissue open in thin patients and closed selectively if the fat was obviously thick or there was dead space, sometimes using drains. When formal clinical trials arrived, investigators and professional societies essentially codified that all the pragmatism into the familiar “close only if ≥ 2 cm” (10). Additionally, meta-analyses and RCTs have shown little benefit for subcutaneous closure with <2cm adipose tissue in the short term (11–14), and even cosmetic scoring systems such as the Patient and Observer Scar Assessment Scale (POSAS), and the Vancouver Scar Scale (VSS) have shown minimal differences across closure techniques (15–17). However, these studies lack long-term follow-up and do not evaluate lower abdominal contour deformities, nor the consequences of Scarpa fascial non-closure.

Although two randomized studies of closure versus non-closure of the Scarpa and Camper’s fascia demonstrated a significant decrease in wound disruption for both vertical and transverse skin incisions with closure (11,18), most guidelines or studies of the surgical technique of cesarean delivery are silent about closure of the Scarpa fascia. It is noteworthy that the emphasis of studies of surgical techniques of cesarean studies has been in short term outcomes, and long-term aesthetic consequences are rarely discussed despite the effect on body image and patient satisfaction.

ABDOMINAL WALL ANATOMY

Understanding the subcutaneous architecture of the anterior abdominal wall is essential to appreciating the pathophysiology of the cesarean apron. Below the skin are three key layers: 1) a superficial areolar fat layer (also called Camper’s fascia); 2) a deep lamellar fat layer; 3) an intervening membranous layer (Scarpa fascia). The muscle fascia is underneath the deep adipose tissue layer (19–26) (Figure 2 A, B)

Figure 2.

Anterior abdominal wall subcutaneous tissue. A. Illustration. Below the skin and dermis, three layers are present: a superficial areolar fat layer (Campers’ fascia) (SF), a membranous layer (Scarpa’s fascia)(SCF), and a deep lamellar fat layer (DF). The Scarpa fascia separates the two fat layers. Below these layers is the deep rectus fascia (RF) that surrounds the abdominal wall rectus muscle (RM). The superficial fat layer, known as Camper’s fascia, consists of turgid and superimposed globular fat cells enclosed within fibrous septa (Reticula Cutis Superficialis-green dots) arranged in a honeycomb-like structure (areolar layer). These septa are predominantly oriented perpendicular to the surface. The deep subcutaneous fat tissue is composed of smaller, fusiform-shaped, flatter, and less defined fat lobes (lamellar layer). The fibroid septa (Reticula Cutis Profunda-red dots) are less consistent and primarily oriented obliquely. The Scarpa fascia is a fibroelastic layer with a membranous appearance. B. Ultrasonic view demonstrating the same layers (illustration and ultrasonic image courtesy of Marco Pelosi III, MD).

Superficial Adipose Tissue Layer, also referred to as Camper’s Fascia

This layer spans from the xiphoid process of the sternum to the inguinal ligaments and continues inferiorly into the thigh. Medially, it merges with Scarpa fascia to contribute to the mons pubis and labia majora in females. Its loose areolar tissue contains globular fat cells arranged in a honeycomb structure, supported by retinacula cutis superficialis—strong, vertically oriented fibrous septa that anchor the dermis to deeper layers (19, 21, 22). These septa keep the skin anchored to the underlying fat and maintain the dimple pattern of skin and transmit small vessels and lymphatics. The layer provides impact distribution, insulation, and vascular support to the abdominal wall. Its thickness correlates with skin thickness and remains relatively stable in obesity (19, 21). The name “Camper’s fascia” recognizes the descriptions of Petrus Camper, a Dutch anatomist (1722–1789) (27). However, this structure is not truly a fascia and does not have organized fibrous or membranous layers. Many anatomists and surgeons consider Camper’s fascia a misnomer, and we believe that this term should be abandoned.

Deep Adipose Tissue Fat Layer

This deeper adipose layer contains smaller, flatter, and more displaceable fat lobules within a network of oblique fibrous septa (retinacula cutis profunda). It has less structural integrity and is prone to shifting, particularly in response to skin or muscle movement. This layer is traversed by vascular and neural structures and increases disproportionately in obesity (19, 20, 22). Cellulite appearance is due to tension from this layer tethering the skin down while fat bulges between. When surgeons place interrupted sutures in subcutaneous tissue, they are effectively approximating fat lobules divided by the retinacula cutis. In necrotizing fasciitis, infections spread rapidly along fascial planes. Fascial septa may transiently limit this spread, but they are often overcome as the infection progresses.

Anatomic studies have shown that the superficial-to-deep fat ratio varies by region. In the hypogastric area, the superficial layer predominates 2:1, while in obese individuals, the deep layer increases markedly (20, 21).

Scarpa Fascia (Membranous Layer)

Scarpa fascia is a fibroelastic, collagen-rich membrane that separates the superficial and deep fat layers. It is continuous, thickest in the lower abdomen, and connects to adjacent structures including the external oblique aponeurosis, linea alba, pubic symphysis, and fascia lata (19, 23, 25). Though traditionally described as limited to the lower abdomen, modern imaging confirms its presence body-wide (23, 24) (Figure 3).

Figure 3.

The superficial fat layer (SF), Scarpa's fascia (SCF), the deep fat layer (DF), the rectus fascia (RF), and rectus muscles (RM) are demonstrated.

Microscopically, Scarpa fascia resembles a dense honeycomb of collagen and elastic fibers. It can resist 2.8–5.5 kg of traction and elongates up to 50%, allowing dynamic movement while maintaining structural support (19, 26). It plays a key role in mechanical homeostasis, skin anchoring, and barrier function (24).

Scarpa fascia also serves as a thin, vascularized flap in reconstructive surgery and has been used successfully in both pedicled and free tissue transfer (26, 28, 29).

Cosmetic and reconstructive surgeons have long recognized the functional and aesthetic significance of Scarpa fascia. Since Lockwood’s foundational work in the early 1990s (30–34), the superficial fascial system has been central to soft tissue shaping and support. Routine Scarpa closure is now standard in abdominoplasty, body lifts, and other contouring procedures, where it reduces ptosis, strengthens wound margins, and enhances aesthetic durability. The divergence between these practices and standard cesarean technique reflects a disconnect between short-term obstetric priorities and long-term body image considerations.

PROPOSED ETIOLOGY AND PATHOPHYSIOLOGY OF THE CESAREAN APRON

We propose that the cesarean apron results from complete or partial failure of closure of the Scarpa fascia, which may lead in susceptible patients to structural changes. We consider three interrelated stages leading to the full development of the bulge:

1. Subcutaneous Fascial Gap Phase

When Scarpa’s fascia is not reapproximated during cesarean closure, the fascial edges retract cephalad and caudad from the incision line. This creates a longitudinal fascial gap—typically along the length of the incision—that disrupts the normal anatomical barrier between the superficial and deep subcutaneous fat layers and the underlying rectus aponeurosis or sheet. The loss of this fascial continuity establishes a potential space for downstream distortion of soft tissue architecture (Figure 4 A, B, C).

Figure 4.

Proposed pathophysiology of the cesarean apron. Subcutaneous fascial gap phase. A) At the start of the cesarean delivery, the skin, superficial fat layer (SF), Scarpa fascia (SCF), and deep fat layer (DF) are divided.. B) At the cesarean section closure, the rectus fascia and skin dermis have been sutured (red lines). The scarpa fascia was left unclosed. C) The upper and lower edges of the Scarpa fascia retract upward and downward from the incision creating a fascial gap along the 15 cm cesarean incision.

2. Pseudolipoma Phase

As healing progresses, the deep subcutaneous fat herniates upward through the fascial gap into the superficial plane. This produces a visible and palpable suprapubic contour deformity, mimicking the appearance of a post-traumatic pseudolipoma—an established consequence of Scarpa fascial disruption in other anatomical contexts (35, 36). The bulging effect is often accentuated by the relative mobility of the overlying tissue (Figure 5).

Figure 5.

Proposed pathophysiology of the cesarean apron in relation to superficial fat (SF), Scarpa fascia (SCF), and deep fat (DF). Pseudolipoma phase. The deep subcutaneous fat pushes through the Scarpa fascial gap, moving upwards and superiorly to create a suprapubic fatty contour deformity resembling the formation of a traumatic pseudolipoma.

3. Scar Depression Phase

With time, the subcutaneous tissue above and below the fascial gap undergoes contraction, producing a transverse depression through which the cesarean scar becomes invaginated. The absence of Scarpa’s fascia allows for the formation of dense scar tissue that traverses unopposed from the skin to the rectus fascia, anchoring the scar and deepening the contour defect (Figure 6).

Figure 6.

Proposed pathophysiology of the cesarean apron. Scar depression phase. A) The subcutaneous tissue contracts above and below the fascial gap, creating a transverse depression. Through this depression the scar will invaginate. B) The loss of the Scarpa fascia results in the formation of unopposed thick scar tissue that spans the entire thickness of the anterior abdominal wall, from the skin to the rectus fascia‥ Superfical fat (SF), Scarpa fascia (SCF), deep fat (DF), scar tissue (ST).

In the inferior part, the retracted lower fascial edge and associated scarring tether the mons pubis, preventing its normal cephalad migration. This results in a protruding mons—particularly when the cesarean scar is wide and indrawn—and may contribute to sagging or descent of the mons pubis, especially when the fascial support is compromised (37, 38) ). Retracted scars below skin level often involve thick fibrotic adherence to the rectus muscle fascia (Figures 7, 8).

Figure 7.

Etiology of the cesarean apron. The Scarpa fascial (SCF) gap also causes the lower fascial edge and the mons pubis fat to retract downward. The invaginated scar blocks normal upward mons fat movement to the lower abdomen. This results in a protruding fatty mons pubis below the cesarean scar, as the scar tissue (ST)hinders the usual fat migration. The deterioration of fascia integrity may also result in ptosis of the mons pubis.

Figure 8.

Degrees of cesarean scar depth when the scar retraction is below the normal skin level. A) Retraction below the skin level, even when mild, leads to deep scarring from the skin to the rectus fascia. B) The patient required a full-thickness resection of the scar. C) Moderate scar depression with retraction below the normal skin level. D) As expected, the scar retraction was associated with deep scarring from the skin to the rectus muscle fascia. E) Deep cesarean scar. F) Full-thickness scarring of the abdominal wall, from skin to rectus fascia, is always present.

Postoperative cesarean scarring may lead to hypertrophic scars, keloids, and scar adhesion. The occurrence of excessive scarring following a cesarean delivery is difficult to estimate, but it may be as high as 41% (39).

Adhesions can form at the scar site, causing pain and a tugging sensation in the lower abdomen. Wound healing involves stages such as hemostasis, inflammation, proliferation, and remodeling. The cesarean scar generally heals within a period of up to six months. This healing process involves the conversion of type III collagen to type I collagen (40). Scar-related complaints encompass itching, pulling, pain, numbness, altered sensation, pricking, burning, tingling, or stinging. There are currently no standardized guidelines for non-invasive procedures in the treatment of localized cesarean scars, such as laser therapy, soft-tissue manual mobilization, or other methods. Scientific data on the efficacy of these procedures is limited (41, 42).

A PROPOSED CLASSIFICATION SYSTEM WITH IMPLICATIONS FOR TREATMENT OF THE CESAREAN APRON DEFORMITY (TABLE)

Table.

Grading of Suprapubic Bulging After Cesarean Delivery and Recommended Management

Grade (Figure)	Clinical Features	Recommended Management
1 (Fig. 10)	Mild suprapubic bulge with visible scar • Minimal fat excess • No diastasis • No scar depression	Liposuction of abdomen and suprapubic region
2 (Fig. 11)	Moderate bulge covering scar • Moderate fat/skin excess (lower abdomen) • No diastasis • Minimal–moderate scar depression	Liposuction, scar release or resection, limited dermolipectomy*
3 (Fig. 12)	• Large bulge extending below scar • Moderate–large fat/skin excess (lower abdomen) • Infraumbilical rectus diastasis • Moderate–deep scar depression	Liposuction, mini-abdominoplasty with scar/apron resection, infraumbilical rectus plication
4 (Fig. 13)	Very large bulge to/below mons pubis • Large fat/skin excess (entire abdominal wall) • Upper and lower rectus diastasis • Deep indrawn scar depression	Liposuction, full abdominoplasty with scar/apron resection, full-length rectus plication

^*Dermolipectomy refers to en block excision of skin and fat.

We have developed a simple, severity-based grading system to facilitate clinical recognition, patient education, and referral decisions. This system has potential value when counseling patients who present with dissatisfaction related to the lower abdominal appearance following cesarean delivery. Each grade is defined by specific anatomical characteristics and has implications for cosmetic treatment. A visual summary of these deformities is available in the linked video:

https://vimeo.com/1115316441/bd0317f207?share=copy

GRADE 1 (Figure 9)

Figure 9.

Cesarean Apron Grade 1: A. Mild suprapubic bulging with a visible cesarean scar. B) Minimal abdominal wall and subcutaneous fat excess. C) Absent abdominal wall diastasis. D) No cesarean scar depression.

1. Mild suprapubic bulging with a visible cesarean scar

2. Minimal abdominal wall and subcutaneous fat excess

3. No abdominal wall diastasis

4. No cesarean scar depression

Liposuction of the abdomen and suprapubic region can often address the fatty contour deformity.

GRADE 2 (Figure 10)

Figure 10.

Cesarean apron Grade 2: A) Moderate suprapubic bulging covering the cesarean scar. B) Moderate abdominal wall subcutaneous fat and skin excess 3. C) Absent abdominal wall diastasis. D) Minimal to moderate cesarean scar depression.

1. Moderate suprapubic bulging covering the cesarean scar

2. Moderate subcutaneous fat and skin excess of the lower abdomen

3. No abdominal wall diastasis

4. Minimal to moderate scar depression

Liposuction, subcutaneous scar release or resection, and limited dermolipectomy (excision of excess skin and fat) are considered for this.

GRADE 3 (Figure 11)

Figure 11.

Cesarean apron Grade 3: A) Large suprapubic bulging hanging below the cesarean scar. B) Moderate to large abdominal wall subcutaneous and skin excess. C) Infraumbilical rectus muscle diastasis. D) From moderate to deep cesarean scar depression.

1. Large suprapubic bulging extending below the cesarean scar

2. Moderate to large lower abdominal fat and skin excess

3. Infraumbilical rectus muscle diastasis

4. Moderate to deep scar depression

Liposuction, mini abdominoplasty with scar and apron resection, and plication of the infraumbilical rectus muscles are recommended for this.

GRADE 4 (Figure 12)

Figure 12.

Grade 4: A) Very large suprapubic bulging hanging at or below the mons pubis. B) Large abdominal wall subcutaneous fat and skin excess. C) Rectus muscle diastasis of the upper and lower abdomen. D) Deep cesarean scar depression.

1. Very large suprapubic bulging extending to or below the mons pubis

2. Large subcutaneous fat and skin excess of the entire abdominal wall

3. Rectus muscle diastasis of both upper and lower abdomen

4. Deep, indrawn cesarean scar depression

Liposuction, full abdominoplasty with scar and apron resection, and plication of the full-length rectus diastasis are recommended for this.

SUMMARY

The cesarean apron deformity is a long-overlooked consequence of routine cesarean delivery techniques. While clinical outcomes such as pain, infection, hematoma, and wound disruption have been extensively studied, long-term structural and aesthetic consequences—particularly those related to fascial support and soft tissue contour—have received little attention.

Complete or partial failure to close Scarpa’s fascia during wound closure has been indicated as a primary contributor to this deformity. Scarpa fascia closure strengthens the wound, minimizes dead space, distributes tension evenly, and reduces the risk of tissue tethering and soft tissue descent. When left open, particularly in patients with thicker subcutaneous layers, it creates a permissive environment for contour distortion, ptosis, and scar depression.

Despite these biomechanical functions, Scarpa fascia is often not closed in obstetric practice. Technical challenges in identification—especially in patients with high BMI—may lead to misplacement of sutures in fat instead of fascia, increasing the risk of fat necrosis. Incomplete closure can result in fascial gaps that compromise tissue support. Techniques such as traction testing with atraumatic clamps or preoperative fascial marking have been proposed to improve accuracy (43).

Closure of a 15-cm Scarpa fascia incision with a running suture tied at each end typically requires 2–3 minutes. The only technical challenges arise in repeat cases, where anatomical distortion and scarring can obscure the central fascia. In contrast to the literature on abdominoplasty (43), high BMI has not posed a feasibility issue. We have not observed increased rates of infection or seroma beyond baseline with routine Scarpa fascia closure.

We propose that routine Scarpa fascia closure be considered in cesarean delivery—not solely to reduce wound complications, but to help prevent this contour deformity. While definitive correction lies outside the scope of general obstetrical and gynecological practice, understanding the etiology and progression of the deformity can improve patient counseling, early recognition, and referral.

Our recommendation for routine Scarpa fascia closure is based on extrapolated evidence and expert opinion. There are no randomized trials or prospective cohort studies demonstrating its impact on long-term contour outcomes and further research is needed.

PATIENT CONSENT

Written informed consent was obtained from all patients for publication of their clinical photographs.