Stages of Labor

FIRST STAGE

From the beginning of labor to the full opening (dilation) of the cervix—to about 10 centimeters.

Initial (Latent) Phase

1. Contractions are irregular at first but become progressively stronger and more rhythmic.

2. Discomfort is minimal but may increase over time.

3. The cervix begins to thin and dilates to about 4 to 5 centimeters.

4. The initial phase lasts an average of 8 hours (usually no more than 20 hours) in a first pregnancy and 5 hours (usually no more than 14 hours) in subsequent pregnancies.

Active Phase

1. The cervix dilates from about 4 centimeters to the full 10 centimeters. It thins and pulls back (effaces) until it merges with the rest of the uterus.

2. The presenting part of the baby (the part of the baby that will deliver first), usually the head, begins to descend into a woman’s pelvis.

3. A woman begins to feel the urge to push as the baby descends, but she should resist it until the cervix is fully dilated. Pushing too early may be unnecessarily tiring and may tear the cervix.

4. This phase averages about 5 to 7 hours in a first pregnancy and 2 to 4 hours in subsequent pregnancies.

SECOND STAGE

From the complete opening of the cervix to birth of the baby: This stage usually lasts about 2 hours in a first pregnancy and about 1 hour in subsequent pregnancies. It may last another hour or more if the woman has been given an epidural injection to relieve pain. During this stage, the woman pushes.

THIRD STAGE

From birth of the baby to delivery of the placenta: This stage usually lasts only a few minutes but may last up to 30 minutes.