Labor is described as having four stages. The first stage is defined as the time from the onset of progressive labor contractions until the cervix is completely dilated. The second stage is from complete dilation of the cervix until the baby is born. The third stage is from the birth of the baby until the placenta is delivered. And finally, the fourth stage is from the delivery of the placenta until the mother's medical condition is stable and safe.
The progression through the four stages of labor varies among women. For some women, labor starts slowly and then speeds up unexpectedly, while for others labor starts rapidly and then slows down. In some cases, our doctors may decide that it is time for your baby to be born even though true labor has not yet started. Induction of labor is the process of starting labor artificially by the use of medication, primarily oxytocin.
The First Stage of Labor - This stage is almost always the longest and may last approximately 8 to 20 hours if this is your first pregnancy, or 5 to 14 hours if you have previously given birth. Early, or latent, labor begins with the onset of regular contractions and ends when your cervix is approximately 3 centimeters dilated. Contractions last approximately 30 seconds and may occur every 10 to 20 minutes from the beginning of one to the beginning of the next, with your uterus relaxing between each one. Much of your time in this early phase of labor may be spent trying to figure out if you are in true labor or not. The most common sign and symptoms of this phase include backache, menstrual-like cramping, indigestion, diarrhea, and bloody show. You may experience all of these or just one or two.
Active labor begins when your cervix is dilated to 3 centimeters and ends when it is fully dilated to 10 centimeters (about 4 inches across). Effacement, or thinning of the cervix, is usually complete or almost complete. Contractions are stronger and longer (30 to 60 seconds) and occur every two to three minutes. You may become serious and quite, focused on only one thing, labor. At this point, support, encouragement, help, and comforting gestures from your partner will be appreciated. You may experience emotional ups and downs throughout your labor, at times even becoming weepy and frustrated. But if you know what to expect and accept labor as it comes, these periods will be easier to tolerate.
During your labor, the nurse or midwife may place her fingertips over your uterus and feel your contractions from the time one begins to the time another begins. This helps determine the timing and strengths of your contractions. If an electronic fetal monitor is used, contractions are measured from the peak of one to the peak of the next.
Membranes can rupture at any time during early or active labor, resulting in a gush, trickle, or leakage of fluid from your vagina. To determine whether your membranes have ruptured, an exam may be done to obtain a sample of amniotic fluid. In some cases, our doctors and nurses may choose to artificially rupture membranes. This procedure may speed up a slow labor. Vaginal exams may also be performed throughout the course of your labor to determine cervical effacement and dilation and/or to apply an internal fetal monitor. This examination may not be done if you are experiencing vaginal bleeding.
At some point during active labor, you may experience irritability, extreme heat or cold, trembling of your arms and legs, nausea, vomiting, and diarrhea. If you have chosen an epidural for pain management, it is generally given when your cervix is dilated to between 3 and 7 centimeters.
Changing positions every 20 to 30 minutes, kneeling on your hands and knees, alternating application of an ice pack and a hot pack, can relieve back pain and a firm massage with the fist or heel of the hand. Breathing and relaxation techniques learned in childbirth preparation classes may provide you additional relief.