The Stages of Labor
Labor is another world for childbirth, the process by which the baby, umbilical cord, and placenta are delivered from the uterus. There are three stages of labor that every mother may experience differently. In a normal pregnancy, labor begins spontaneously sometime between the 37th and the 42nd week of pregnancy.
Most of labor is not spent in the hospital pushing. The first, longest stage of labor is passive on the mother’s part. During this stage, contractions of the uterus slowly cause the cervix—the tissue that separates the uterus from the vagina—to thin and widen to accommodate the baby’s head. Eventually, once the cervix has fully dilated, the active stage of labor begins. The mother begins pushing and, within a few hours, the baby is delivered followed by the placenta.
The whole process may take around 22 hours for first-time mothers and 15 hours for mothers who have given birth before. However, the duration of labor varies widely. There are extremes on both sides, with some mothers delivering after just a few hours of contractions and others taking days. Extremely fast labor, when a baby is born after less than 3 hours of contractions, is called precipitous delivery. Prolonged labor may be diagnosed as “failure to progress” and require medical intervention such as a c-section.Stages of Labor
You may know that you are getting close to labor if your due date is approaching, your baby has moved into the vertex position, or your doctor has noticed your cervix beginning to dilate. Signs that you are going into labor include feeling regular contractions and pain in the belly and lower back. You may experience some contractions before going into true labor—the difference is that contractions that signal labor are regular and get stronger. Additionally, you may see “bloody show,” a bloody mucous discharge, or your water may break. Your “water breaking” is when the amniotic sac that surrounds the baby in the womb ruptures. When this happens, you will notice a watery discharge or sensation.First Stage or Early Labor
The first stage of labor, also called early labor, is by far the longest. It begins at the onset of labor and continues until the cervix is fully dilated. Cervical dilation is critical—the cervix is an extremely narrow passageway between the uterus and vagina that needs to stretch and thin to allow the baby to fit through. For reference, the cervix needs to grow from 1 inch, the size of a small grape, to 10 inches, the size of a grapefruit, during this stage.
This early stage is divided into two phases, the latent and the active phases. It usually takes around 20 hours from start to finish for first-time mothers.
The latent phase of labor lasts anywhere from 5 to 20 hours or more and is complete when the cervix is dilated to about 4 centimeters. Cervical dilation is measured by feeling the cervical opening with two fingers. Contractions are mild, and pain is minimal during this phase. Most mothers stay home during the latent phase, as it is the longest phase and medical attention is not usually needed.
The active phase of labor lasts an average of 2 to 8 hours during which time contractions become stronger and more rhythmic, signaling that it’s time to go to the hospital. Throughout the active phase, the cervix becomes fully dilated to 10 centimeters and the baby’s head descends into the pelvis. Labor gets more and more painful as the cervix nears complete dilation. Widening from 6 centimeters to 10 centimeters, called the transition phase, can be especially difficult because it often happens within an hour. Pain management methods like epidurals and pain medications may be used from the active phase onward.
Doctors and nurses in the delivery unit closely monitor fetal heart rate and cervical dilation during the first stage of labor. This is so that they can intervene if the baby becomes distressed or the labor is not progressing. If the amniotic sac has not ruptured, doctors may perform an amniotomy to rupture the membrane.Second Stage or Active Labor
The second stage, also called active labor, is the pushing stage of labor. The baby passes all the way through the cervix, through the pelvis and birth canal, and out through the vaginal opening. On average it takes 1 to 3 hours from the time that the cervix becomes fully dilated to the birth of the baby. Since the baby’s head has moved from the uterus to the birth canal, uterine contractions must be replaced by the mother pushing herself.
Midwives, doulas, and family members may be especially important during active labor to help coach the mother through the hard work of pushing. During the second stage, doctors watch carefully for signs of complications affecting either the mother or child. They closely monitor the baby’s heart rate and position to make sure that he or she is not in distress or stuck.Third Stage
The third stage consists of the delivery of the placenta, also known as the afterbirth. Usually it takes only a few minutes for the placenta to follow the baby. While waiting for the placenta, doctors continue to check on the health of the baby and mother, including the baby’s heart rate and vital signs. If the placenta is not delivered, it must be surgically removed to prevent serious health complications.
Every labor takes a different amount of time for reasons that doctors cannot entirely explain. In general, though, first-time mothers take a longer time to give birth than those who have given birth before.
Some factors that may lengthen labor include giving birth to twins, having a large baby, being overweight or obese, or having a baby that is in an abnormal position. Conversely, standing and walking may shorten the first stage of labor.
Epidural anesthesia can slow the second stage of labor by up to an hour. An epidural is an injection of anesthetic into the mother’s lower spine that relieves the pain of labor—this may slow the second stage of labor because the mother is less able to control her pushing. This also means that epidurals are associated with operative delivery, namely the use of forceps, to assist labor. However, evidence shows that epidurals are the best at relieving the pain of labor and that fetal outcomes are the same for epidurals versus other pain relief methods or no pain relief. In the end, childbirth is extremely painful and using or not using an epidural is a personal decision.
What about induced labor? Drugs like Pitocin (oxytocin) can be used to induce labor into starting. Sometimes, doctors induce labor to start because there is a medical reason to do so. For example, a doctor may induce labor if the mother has preeclampsia or diabetes, there is not enough amniotic fluid, or if the amniotic sac has ruptured but labor has not begun on its own. Recently, elective induction has become more popular—that is, inducing labor without a medical reason. Induction may slow the process of labor, and it is still unclear to researchers if elective induction creates more risks than benefits in normal pregnancies.
Pitocin can also be used to expedite a spontaneous labor that doctors think is taking too long to progress, Pitocin does not seem to improve pregnancy outcomes apart from shortening labor. By strengthening contractions, Pitocin can shorten labor by up to two hours, which some women may decide is right for them.
“Duration of spontaneous labour in ‘low-risk’ women with ‘normal’ perinatal outcomes: A systematic review” by Edgardo Abalos et al., European Journal of Obstetrics & Gynecology and Reproductive Biology, 2018.
This study is a review of 37 previous studies that recorded the duration of the first and second stages of labor. The authors analyzed this data and present the averages and top-limits for the duration of labor for both first-time (nulliparous) and non-first-time mothers (multiparous). However, they found that labor times for women with good outcomes for their babies varied greatly, suggesting that doctors may not need to take action to speed up labors that take longer than average unless other worrying factors are present, or the labor is taking an extremely long time.
“Obesity in Pregnancy: Altered Onset and Progression of Labour” by Annick Bogaerts et al., Midwifery, 2013.
Another literature review, this study was based on the fact that obesity is a health problem that greatly affects the global population and negatively affects pregnancy outcomes. The study found that obese mothers are more likely to have post-term pregnancies and a prolonged first stage of labor, an important consideration for health care providers.
“Changes in labor patterns over 50 years” by Katherine Laughon et al., American Journal of Obstetrics & Gynecology, 2013.
The authors of this study asked if the duration of labor has changed in the United States since the 1960s. They found that the first stage of labor is on average 2.6 hours longer for women today than it was for women in the 1960s. How could this be? When researchers controlled for other characteristics such as an increase in maternal weight and age, they concluded that changes in medical treatment led to the longer labors seen today. On the one hand, epidurals, cesarean sections, and Pitocin are more commonly used today. On the other hand, episiotomies and operative deliveries, i.e. use of forceps and vacuums, is less commonly used today. Researchers will continue to study the benefits and risks of these interventions. A key takeaway from this study for health care providers is that they might expect labor to take longer than traditional, outdated guidelines suggest.