There are four stages of labor.
First Stage of Labor
Thinning (effacement) and opening (dilation) of the cervix
During the first stage of labor, contractions help your cervix to thin and begin to open. This is called effacement and dilation. As your cervix dilates, your health care provider will measure the opening in centimeters. One centimeter is a little less than half an inch. During this stage, your cervix will widen to about 10 centimeters. This first stage of labor usually lasts about 12 to 13 hours for a first baby, and 7 to 8 hours for a second child.
The first stage of labor has three parts:
1. Early labor
Your cervix opens to 4 centimeters. You will probably spend most of early labor at home. Try to keep doing your usual activities. Relax, rest, drink clear fluids, eat light meals if you want to, and keep track of your contractions. Contractions may go away if you change activity, but over time they'll get stronger. When you notice a clear change in how frequent, how strong, and how long your contractions are, and when you can no longer talk during a contraction, you are probably moving into active labor.
2. Active labor
Your cervix opens from 4 to 7 centimeters. This is when you should head to the hospital. When you have contractions every 3 to 4 minutes and they each last about 60 seconds, it often means that your cervix is opening faster (about 1 centimeter per hour). You may not want to talk as you become more involved in dealing with your contractions. As your labor progresses, your bag of waters may break, causing a gush of fluid. After the bag of waters breaks, you can expect your contractions to speed up.
Slow, easy breathing is usually helpful at this time. Focusing on positive, relaxing images or music may also be helpful. Changing positions, massage, and hot or cold compresses can help you feel better. Walking, standing, or sitting upright will help labor progress. Relaxing during and between contractions