When you think of labour pains, you tend to think of contractions. But you can also get pains elsewhere, especially in your back.
Back pain tends to linger in between the contractions but might well happen throughout your labour.
It is more likely to happen when your baby is in certain positions, like back to back with you. The best thing to do to relieve this back pain is to get onto all fours. That decreases the pressure on your cervix and gives good counter pressure for your lower back.