We all have a separation between our 6 pack rectus abdominal muscles. If the separation is more than 2.7cm, then it is considered to be ‘diastasis recti’. It can occur in pregnancy, but also in men who lift weights without engaging their core and in newborns. It’s measured in finger widths. A 1 - 2 finger separation is pretty common and 3 - 4 finger separation is considered ‘big’.
There is no way to know how much your separation is/will be until after you give birth. It’s very very common in pregnancy, we see it all the time, it’s not painful and definitely not something to worry about for the moment. We resolve any diastasis issues in postnatal workouts!
It can happen for many reasons. For some people who have a really strong core, they’ve only focused on building strength in their abdominals but haven’t focused on flexibility. Our abs, just like our hamstrings ideally are strong and flexible. In pregnancy, ab muscles have to stretch to accommodate baby and if they’re not flexible, the cartilage between them begins to separate instead. For others it occurs just as the belly grows bigger, or not being careful enough about turning over to one side and getting up form laying down. But you could be really careful and still have diastasis!
There are many good reasons to try to minimize the separation - it weakens abs, can cause low back pain, it affects baby’s position and causes the little pooch that many people have after kids. But if you do have it, it should clear up on it’s own 6 weeks postpartum. Your doc will let you know at your post-birth check up if you have it. If it you do have it, then we would start to make modifications in postnatal exercise.
While you’re pregnant, exercises to avoid are any ab work that causes your belly to bulge and cone - sit ups, crunches, boat pose. But the biggest culprit is lurching straight up from laying down rather than turning on your side. The best thing you can do to prevent a separation, a separation from worsening or to heal the separation is the ab exercise we do in class - belly pulls on all fours, and the breathing exercise - nose throat chest belly.
Make sure your core (diaphragm, pelvic floor, transverse abs and multifidus muscles) are working together in sync. That means, hands to belly, as you inhale, feel belly expand, lengthen and release pelvic floor. As you exhale, feel transverse abs (the ones that go all the way around your waist) engage and draw in and feel slight lift of pelvic floor. If you're pregnant, you can do this exercise on all fours. If you're postnatal, on your back with knees bent and feet on the floor.