Diastasis Recti (DR) is a common condition that affects the abdominal muscles during and after pregnancy. This condition involves the partial or complete separation of the rectus abdominis muscles, commonly known as the “six-pack” muscles, which results in a persistent bulge or “pooch” in the abdomen. Up to 60% of women experience some degree of this separation after childbirth. Understanding the anatomical cause of Diastasis Recti is the first step toward effective management and recovery.
Defining Diastasis Recti and Its True Cause
Diastasis Recti occurs when the two bands of the rectus abdominis muscles pull apart from the linea alba, the dense connective tissue that runs down the center of the abdomen. This separation is not a muscle tear but rather a widening and thinning of this midline fascia. The primary cause is the immense, sustained pressure placed on the abdominal wall during pregnancy, not a surgical procedure.
The expanding uterus, especially during the third trimester, creates intense intra-abdominal pressure (IAP) that pushes the abdominal contents outward. Simultaneously, hormonal changes contribute to the softening of the connective tissue. The hormone relaxin loosens the ligaments and fascia throughout the body, including the linea alba, making it more pliable and susceptible to widening.
Nearly all pregnant individuals exhibit some degree of this abdominal wall separation by the end of the third trimester. This stretching of the fascia is a normal, physiological adaptation. Diastasis Recti is diagnosed when this stretched connective tissue loses its ability to recoil and create tension postpartum, typically defined as a separation wider than two finger-widths or 2 centimeters.
The C-Section Connection
A C-section delivery does not cause Diastasis Recti; the separation of the rectus abdominis muscles occurs during pregnancy due to the growing uterus and hormonal factors. C-section is simply the method of delivery, not the underlying cause of the fascial widening.
The common C-section technique, known as the Pfannenstiel or “bikini-line” incision, is a low-transverse cut made just above the pubic symphysis. This incision cuts through the skin, fat, and fascia layers, but the rectus abdominis muscles are typically separated and pulled apart gently to the sides, not cut in half. The surgical incision is far lower than the area where the most significant DR separation often occurs, which is around the umbilical region.
Having a C-section can complicate the recovery process of pre-existing DR. The surgical wound requires a healing period that restricts early core engagement. Scar tissue that forms at the incision site can tether the fascia and muscle layers, potentially impacting the function and recovery of the abdominal wall above the scar. This dual recovery process often necessitates a more cautious approach to postpartum core strengthening.
Identifying and Assessing Diastasis Recti
A simple self-assessment can help identify if a separation is present, though it should be performed gently and ideally not until about six to eight weeks postpartum.
Performing the Check
Lie on your back with your knees bent and feet flat on the floor. Place one hand behind your head for support, and the fingers of your other hand vertically across your midline, pointing toward your pelvis.
As you tuck your chin and lift your head slightly—just enough to engage your abdominal muscles—gently press your fingers down into the midline. Feel for the gap between the two strips of muscle that tighten on either side. Assess the width of the gap using the number of fingers that fit snugly between the muscle edges.
Assessing Width and Depth
It is helpful to check for the separation at multiple points: directly at the belly button, two inches above it, and two inches below it. Beyond the width, the depth of the separation is an equally important indicator of functional integrity. If your fingers sink deeply into a soft, squishy space, it suggests poor tension in the linea alba, regardless of the gap’s width.
Safe Management and Recovery
The recovery pathway for Diastasis Recti, especially following a C-section, must prioritize surgical healing before intense core work begins. A healthcare provider’s clearance, typically around six to twelve weeks postpartum, is necessary before starting a targeted exercise program. The early focus should be on gentle, foundational exercises that restore connection to the deep core.
The Transverse Abdominis (TA) muscle, which acts like a natural corset, is the primary target for rehabilitation. Exercises that focus on deep, diaphragmatic breathing combined with a gentle drawing-in of the abdominal wall help activate the TA without straining the recovering fascia or surgical site. Activities that increase IAP, such as traditional crunches, sit-ups, planks, or heavy lifting, must be avoided in the early stages as they can put excessive outward pressure on the midline and worsen the separation.
Consulting a pelvic floor physical therapist (PFPT) is the most evidence-based step for a safe and effective recovery. A PFPT can provide a personalized program that includes scar tissue mobilization techniques, which can improve mobility and reduce fascial tethering caused by the C-section incision. They ensure that core strengthening progresses safely, managing the simultaneous recovery of the surgical incision and the fascial separation.