Answer: If you’re pregnant and experiencing rib pain, you may be wondering if it’s normal. Rib pain during pregnancy is common, especially in the third trimester as your baby grows. But the pain can start pretty early on in your pregnancy, too. Pregnancy rib pain can be the result of your baby physically kicking you in the ribs, stretching out under your ribs, or just moving by your ribs. The pain can also be caused by your muscles stretching out. In some rare cases, it might be caused by a medical complication.