Having a baby involves profound physical changes, and one common adjustment is postpartum rib flare. This condition describes the outward and upward protrusion of the lower rib cage that can persist long after delivery. Many new mothers notice that their bra bands fit tighter or their torso appears wider than before pregnancy. Understanding that this is a predictable physical outcome of gestation provides a starting point for effective recovery. With specific, focused core re-education and a renewed awareness of posture, it is possible to guide the rib cage back toward a more neutral alignment.
Anatomical Shifts Causing Postpartum Rib Flare
The primary cause of rib flare is the mechanical pressure exerted by the growing fetus and uterus during the pregnancy. As the uterus expands, it pushes the abdominal organs upward, which in turn displaces the diaphragm, the primary muscle of breathing, and the rib cage itself. This sustained internal pressure forces the ribs to widen and subtly tip into an expanded, “inhaled” position to create necessary space for both the baby and the lungs. Research suggests the rib cage can expand by an average of 2 to 3 inches over the course of the pregnancy.
This mechanical change is compounded by the hormonal environment of pregnancy, which loosens connective tissues throughout the body. The abdominal muscles, particularly the rectus abdominis, are stretched significantly, often resulting in diastasis recti. These stretched muscles lose their ability to provide the necessary support and tension to keep the rib cage drawn down and stabilized. Without this muscular counter-tension, the lower ribs are left in their expanded, flared position even after the baby is born.
Foundational Breathing and Core Re-education
The first step in correcting rib flare is re-establishing the proper function and coordination of the deep core muscles, starting with breathing mechanics. This foundational work centers on 360-degree breathing, which aims to restore the diaphragm’s full range of motion. Begin by lying on your back with your knees bent and feet flat, or with your feet resting on a chair or bench in a 90/90 position, ensuring your rib cage feels heavy and relaxed on the floor.
On the inhale, focus on allowing the breath to expand laterally into the sides and back of the lower rib cage, rather than pushing the belly or chest upward. The diaphragm should descend gently, creating expansion in all directions. The exhale is where the corrective action occurs; breathe out slowly, gently drawing the lower ribs down and in toward the pelvis. This movement encourages the re-engagement of the deep abdominal muscles, particularly the transverse abdominis and obliques, which help pull the ribs back into a more neutral alignment.
Once this breathing pattern is established, integrate gentle core movements to practice maintaining a “stacked” alignment, where the rib cage sits directly over the pelvis. A simple exercise involves a gentle pelvic tilt, rocking the pubic bone slightly toward the belly button on the exhale while keeping the rib cage connected. Another helpful strategy is a supine rib tuck, where you focus solely on drawing the front bottom ribs down toward the floor as you exhale completely, without crunching the neck or upper back. These early-stage exercises should be slow, controlled, and focused on alignment and coordination.
Integrating Alignment into Daily Activities
True core recovery and the resolution of rib flare depend on applying the principles of alignment learned through floor exercises to everyday functional movements. This involves constantly aiming to maintain the stacked position of the rib cage over the pelvis throughout the day.
Feeding and Sitting Alignment
When sitting to feed the baby, whether by breast or bottle, use pillows under the arms and a small pillow or rolled towel for lumbar support to prevent slouching and the resulting forward rib thrust.
Lifting Techniques
When lifting the baby or car seat, ensure you hinge at the hips and bend your knees instead of rounding your back. Exhale as you initiate the lift, which naturally engages the deep core muscles and helps stabilize the torso, preventing the ribs from flaring upward under pressure. Keep the load, such as the car seat or the baby, as close to your body as possible to reduce strain on the back and utilize leg strength more effectively.
Walking and Carrying
For activities like pushing a stroller, focus on walking tall with the ribs aligned over the hips, avoiding the common tendency to lean forward or arch the lower back. If you carry your baby in one arm or on a hip, make a conscious effort to switch sides frequently to distribute the load evenly and prevent asymmetrical rib flaring. Consistently practicing this mindful movement integrates core stability into your new physical demands.
Recognizing When Professional Guidance is Necessary
While self-guided core re-education is effective, there are indicators that professional assessment is necessary for safe and complete recovery. If you continue to experience persistent pain—such as chronic low back, neck, or shoulder discomfort—after several months of consistent practice, a specialist can help identify compensatory patterns. Similarly, a lack of noticeable progress in reducing the rib flare or improving core strength after three to four months of focused work suggests a need for individualized guidance.
The presence of concurrent, severe issues, such as a significant and persistent diastasis recti or symptoms of pelvic floor dysfunction, including urinary incontinence or pelvic pressure, warrants expert evaluation. A Pelvic Floor Physical Therapist (PT) is specifically trained to assess the entire core canister, including the diaphragm, rib cage, abdominal wall, and pelvic floor, as a connected system. Consulting a PT allows for the creation of a tailored recovery plan that addresses all contributing factors, ensuring the most complete and functional postpartum recovery.