Abdominal Crunches During Pregnancy - Are They Safe?

When it comes to movement in pregnancy, one of the most common questions I’m asked is: “Is it safe to do abdominal flexion while pregnant?”

The short answer? It depends.

During pregnancy, your body undergoes incredible changes to support your baby. One of these is the natural stretching of your abdominal wall as your uterus grows. Over time, the linea alba (the connective tissue down the midline of your abs) thins and widens — this is called diastasis recti. Excessive or repetitive abdominal flexion (think crunches or sit-ups) can place additional strain on this tissue and potentially worsen abdominal separation.

So, does that mean all flexion is off-limits? Not necessarily. Early in pregnancy, some gentle flexion-based exercises can be safe if performed mindfully, with good technique, and if your body feels comfortable. But as your pregnancy progresses, most traditional flexion should be avoided in favour of core-stabilising movements that:

• Strengthen the deep abdominal muscles (especially the transverse abdominis).

• Protect the pelvic floor.

• Support posture and spinal alignment.

In my studio, I focus on safe modifications — such as seated core activation, supported breathing patterns, and functional movements that help mums-to-be feel strong without unnecessary strain.

Ultimately, it’s not about avoiding movement, but about choosing the right kind. Every pregnancy is unique, which is why personalised guidance from a qualified pre-natal Pilates instructor is invaluable.