The start of labour is called the latent phase. This is when your cervix becomes soft and thin as it gets ready to open (dilate) for your baby to be born.
For this to happen, you’ll start having contractions (tightening's), which may be irregular and vary in frequency, strength and length. You may get lots of regular contractions and then they may slow down or stop completely.
When you have a contraction, your womb tightens and then relaxes. For some people, contractions may feel like extreme period pains. Some women and birthing people say they feel pain in their back and thighs instead of, or as well as, pain in the front of their bump.