What is rib flaring?
Rib pain during pregnancy can be a persistent problem, especially during the third trimester. Your rib cage may feel mildly sore or extremely tender and bruised. You may have discomfort on either side, or both sides, though it is commonly worse on the right side of the ribs. Pain occurs in and under the ribs as your uterus grows.
What causes rib flaring?
The demand for oxygen is increased in pregnancy because the basal metabolic rate and the mass of the expectant mom increase as well. It is estimated that a woman will require about 20% more oxygen than normal at term. She also exhales more carbon dioxide which triggers the already sensitive respiratory system to increase the respiratory rate slightly. Hence, it is this lowering of the carbon dioxide that leads to pregnant women to becoming breathless on activity. Your diaphragm will have to work harder which may result in the feeling of ‘getting a stitch’ as the diaphragmatic muscles fatigue.
Many expectant women will experience the baby beginning to press up under her ribs and chest. This is the uterus ascending as the abdomen becomes stretched upward and outward with the growing baby. It may also make you feel short of breath. This ascending uterus thus progressively obstructs the descent of the diaphragm, which is needed for deep breathing. It can force the diaphragm upwards by at least 4cm towards the end of pregnancy. Hence this rising pressure pushes the rib cage out sideways and forwards, resulting in pain in the front of the lower ribs, also known as rib flare. This pressure on your ribs and diaphragm may also result in shoulder pain, because there are nerves in the diaphragm which can refer pain into the shoulders.
As your breasts become larger, they also place pressure on your ribs. During pregnancy, your breasts may increase by one full cup size or more. The extra weight pulls your shoulders forward and down, and places strain on the upper back, neck, and often results in pain around the rib cage.
As the baby grows, motion of the ribs and thoracic spine becomes restricted affecting chest and diaphragm movement. The lymphatic system requires the diaphragm to work as a pump to aid the flow of lymph back into the venous system and heart. Fluid and electrolyte balance is affected leading to fluid retention in the body (as seen clearly at the ankles).
What can I do to get relief?
Rib pain during pregnancy can cause the greatest discomfort when you are in a sitting position. Practicing good posture is especially important. Try to make sure that you sit up straight with your shoulders back. Slouching will compress your abdomen and result in more pain.
Here is a really effective exercise for temporary relief. Stand facing a wall. With your feet 40cms from the wall, cross your arms in front of your face. Then lean your crossed arms on the wall sliding them up the wall above your head and stretching yourself up as far as possible. Hold the position for as long as comfortable. This lifts the diaphragm and rib cage up off the uterus. Practicing doorway chest stretches can also be helpful because they, too, will help rotate the shoulders up and back, which can also help lift the ribs away from the uterus.
It is especially important to have a supportive bra that is not too tight. Under wire bras may put too much extra pressure on your ribs. Now may be a good time to invest in a good nursing bra. They usually offer nice support without being too tight and will be useful once your baby is born. Stretching and prenatal yoga are great for keeping your body long and loose. The less compressed you are, the less your rib cage will hurt.
Breathing and relaxation exercises may also be effective. There are a variety of hands on techniques that can help to gently stretch and lift your ribs away from the uterus. Applying these techniques to your breasts, chest and abdomen, can really relieve a lot of pain and pressure from your body, though you will need a friend or partner to help you. Scheduling a visit to your physiotherapist may also help provide relief from rib pain during pregnancy. A combination of soft tissue work, gentle mobilizations, postural training, Pilates, and support/kinesiotape can be very effective.
NOTE: If you are having rib and flank pain that goes through to your back, and or burning or pain with urination, you should contact your health care provider. This could be an indication of a urinary tract infection.
Megyn Robertson (MSc Physiotherapy)
Broadacres Physiotherapy and Craighall Park