9.2: Childbirth

Learning Objectives

1. Describe the physiological and hormonal processes that initiate labor.
2. Identify and explain the three stages of vaginal childbirth.
3. Compare and contrast medical interventions used during labor and delivery.
4. Identify common signs of labor onset.
5. Summarize how cultural values influence childbirth practices.

Onset of Labor

Childbirth typically occurs within a week of a woman’s due date, unless the woman is pregnant with more than one fetus, which usually causes her to go into labor early. As a pregnancy progresses into its final weeks, several physiological changes occur in response to hormones that trigger labor.

A common sign that labor is beginning is the so-called “bloody show.” During pregnancy, a plug of mucus accumulates in the cervical canal, blocking the entrance to the uterus. Approximately 1–2 days before the onset of true labor, this plug loosens and is expelled, along with a small amount of blood.

As labor nears, the mother’s pituitary gland produces oxytocin. This begins to stimulate stronger, more painful uterine contractions, which—in a positive feedback loop—stimulate the secretion of prostaglandins from fetal membranes. Like oxytocin, prostaglandins also enhance uterine contractile strength. The fetal pituitary gland also secretes oxytocin, which further increases prostaglandins.

And the stretching of the cervix by a full-term fetus in the head-down position is regarded as a stimulant to uterine contractions. Combined, these stimulate true labor. ¹⁰

Stages of Birth for Vaginal Delivery

The First Stage

The first stage of labor consists of three phases: early labor, active labor, and transitional labor. The first stage of labor is typically the longest. During this stage, the cervix, or opening to the uterus, dilates to 10 centimeters, or just under 4 inches, and effaces, or thins out, to accommodate dilation. This may take around 12-16 hours for first children or about 6-9 hours for women who have previously given birth. Labor may also begin with a discharge of blood or amniotic fluid (ACOG, 2020).

Figure \(\PageIndex{1}\): Early cervical dilation. Image by OpenStax is licensed under CC BY 3.0

Phase 1: Early labor

In early labor, uterine contractions signify that labor has begun. These contractions may initially last about 30 seconds and be spaced 5 to 20 minutes apart. Pain during the early labor phase differs from woman to woman, but many report contractions not being too painful (Low & Moffat, 2020). It is recommended to spend this phase of the first stage at home, resting or engaging in light activity. Some women experience false labor or Braxton-Hicks Contractions, especially with the first child. These may come and go. They tend to diminish when the mother begins walking around. Real labor pains tend to increase with walking. In one out of 8 pregnancies, the amniotic sac or water in which the fetus is suspended may break before labor begins. In such cases, the physician may induce labor with the use of medication if it does not begin on its own in order to reduce the risk of infection. Normally, this sac does not rupture until the later stages of labor (ACOG, 2020).

Table \(\PageIndex{1}\): Early labor

Contraction Timing	Cervical Dilation	Duration of phase
30-60 seconds	up to 4 or 5	6-12 hours on average, but can last more than 24 hours

Phase 2: Active labor

Once contractions increase in duration and frequency to more than a minute in length and about 3 to 4 minutes apart, the woman is considered to be in active labor. Typically, doctors advise that they be called when contractions occur every 5 minutes. Hospitals and birth centers vary in how active labor is defined for admission - some define it as when the cervix has dilated to 4 or 5 centimeters, while others assess based on dilation, effacement, contractions, and pregnancy classification. It is during active labor that a woman may feel the need for pain medication or may use techniques to help her deal with the pain. Active labor lasts, on average, between 3 and 8 hours (ACOG, 2020).

Table \(\PageIndex{2}\) : Active labor

Contraction Timing	Cervical Dilation	Duration of phase
60+ seconds in length occurring at least every 5 minutes	from 4/5 cm to 7 cm	between 3 and 8 hours

Phase 3: Transition

Transition labor is the final phase of the first stage of labor, marking the shift from active labor to the second stage. It begins when the cervix dilates from 7 to 10 centimeters in diameter. During this intense phase, contractions become very strong, frequent, and close together, often occurring every 2 to 3 minutes and lasting 60 to 90 seconds each. These contractions may feel overwhelming and are accompanied by pressure in the lower back or pelvis as the baby moves into position for delivery. Transition labor is often considered the most challenging part of labor but is also the shortest, typically lasting between 15 minutes and 3 hours (ACOG, 2020).

Table \(\PageIndex{3}\) : Transitional labor

Contraction Timing	Cervical Dilation	Duration of phase
60-90 seconds in length occurring every 2-3 min	from 7 to 10 cm	15 minutes to 3 hours

The Second Stage

The passage of the baby through the birth canal is the second stage of labor. This stage typically lasts between 10 and 40 minutes. Contractions usually come about every 2-3 minutes. The mother pushes and relaxes as directed by the medical staff. Normally, the head is delivered first. The baby is then rotated so that one shoulder can pass through, followed by the other shoulder. The rest of the baby passes through quickly. At this stage, an episiotomy, or incision made in the tissue between the vaginal opening and anus, may be performed to avoid tearing the tissue of the back of the vaginal opening (Mayo Clinic, 2016). The baby's mouth and nose are suctioned out. The umbilical cord is clamped and cut. ¹²

Figure \(\PageIndex{2}\): Full dilation and expulsion of the newborn. Image by OpenStax is licensed under CC BY 3.0

The Third Stage

The third and final stage of labor is relatively painless. During this stage, the placenta or afterbirth is delivered. This is typically within 20 minutes after delivery. If an episiotomy was performed, it is stitched up during this stage. ¹⁴

Figure \(\PageIndex{3}\): Delivery of the placenta and associated fetal membranes. Image by OpenStax is licensed under CC BY 3.0.

Additional Considerations

More than 60% of women giving birth at hospitals use an epidural anesthesia during delivery (ACOG, 2020a). An epidural block is a regional analgesic that can be used during labor and alleviates most pain in the lower body without slowing labor. The epidural block can be used throughout labor and has little to no effect on the baby. Medication is injected into a small space outside the spinal cord in the lower back. It takes 10 to 20 minutes for the medication to take effect. An epidural block with stronger medications, such as anesthetics, can be used shortly before a Cesarean Section or if a vaginal birth requires the use of forceps or vacuum extraction. ¹⁶

Women giving birth can also receive other pain medications (although medications given through injection can have negative side effects on the baby). In emergency situations (such as the need for a C-section), women may be given general anesthesia. They can also choose not to utilize any pain medications. That is often referred to as natural childbirth.

Figure \(\PageIndex{4}\): Natural childbirth. Image by U.S. Army Alaska is licensed under CC BY 2.0

Women can also use alternative positions (including standing, squatting, being on hands and knees, and using a birthing stool) during labor and even deliver in tubs of warm water to help relieve the pain of childbirth.

Medical Interventions in Childbirth

Sometimes women cannot go into labor on their own and/or deliver vaginally. Let’s look at induction of labor and Cesarean Sections.

Sometimes a baby’s arrival may need to be induced before labor begins naturally. Induction of labor may be recommended for various reasons when there is concern for the health of the mother or the baby. For example:

• The mother is approaching two weeks beyond her due date, and labor has not started naturally
• The mother’s water has broken, but contractions have not begun
• There is an infection in the mother’s uterus
• The baby has stopped growing at the expected pace
• There is not enough amniotic fluid surrounding the baby
• The placenta peels away, either partially or wholly, from the inner wall of the uterus before delivery
• The mother has a medical condition that might put her or her baby at risk, such as high blood pressure or diabetes (Mayo Clinic, 2014).

A Cesarean Section (C-section) is surgery to deliver the baby through the mother's abdomen. In the United States, about one in three women have their babies delivered this way (Martin et al., 2015). Most C-sections are done when problems occur during delivery unexpectedly. These can include:

• Health problems in the mother
• Signs of distress in the baby
• Not enough room for the baby to go through the vagina
• The position of the baby, such as a breech presentation, where the head is not in the downward position.

Figure \(\PageIndex{5}\): A woman receiving a C-section. Image by Tammra M is licensed under CC BY 2.0

Figure \(\PageIndex{6}\): A baby being delivered by C-section. Image by Patricia Prudente on Unsplash

C-sections are also more common among women carrying more than one baby. Although the surgery is relatively safe for mother and baby, it is considered major surgery and carries health risks. Additionally, it also takes longer to recover from a C-section than from vaginal birth. After healing, the incision may leave a weak spot in the wall of the uterus. This could cause problems with an attempted vaginal birth later. In the past, doctors were hesitant to allow a vaginal birth after a C-section. However, now more than half of women who have a C-section go on to have a vaginal birth later. ²⁰ This is referred to as a Vaginal Birth After Cesarean (VBAC).

Cultural Considerations

Although childbirth is a universal biological event, cultural practices surrounding the birth process can differ significantly across societies. In many cultures, birth is not solely a medical procedure but also a deeply symbolic and communal experience. For example, some Indigenous and African cultures prioritize home births with traditional birth attendants, incorporating rituals and ceremonies that mark spiritual and familial milestones (Davis-Floyd, 2003). In contrast, in many Western societies, the medicalization of childbirth is common, with hospital births and medical interventions such as epidurals and cesarean sections being emphasized (Rothman, 2003). These varying approaches reflect different cultural values about health, medicine, and the role of technology in birth.

Cultural beliefs also influence the support systems during labor and the roles of family members. In certain Asian cultures, it is common for the extended family to be present during childbirth, with an emphasis on maintaining harmony and balance throughout the process (Kleinman & Benson, 2006). On the other hand, in some Western and European cultures, the presence of the father or partner during labor is often encouraged, while in other cultures, it may be restricted or discouraged (Grotevant, 2011). Additionally, postpartum practices, such as dietary restrictions and the prescribed length of rest, vary widely across cultures. These cultural differences highlight how the childbirth experience, although universally shared, is shaped by distinct social norms, practices, and beliefs.

References, Contributors and Attributions

10. 28.4 Maternal Changes During Pregnancy, Labor, and Birth by Lindsay M. Biga, Sierra Dawson, Amy Harwell, Robin Hopkins, Joel Kaufmann, Mike LeMaster, Philip Matern, Katie Morrison-Graham, Devon Quick, and Jon Runyeon is licensed under CC BY-NC-SA 4.0

12. Lifespan Development: A Psychological Perspective (page 60) by Martha Lally and Suzanne Valentine-French is licensed under CC BY-NC-SA 3.0

14. Lifespan Development: A Psychological Perspective (page 60) by Martha Lally and Suzanne Valentine-French is licensed under CC BY-NC-SA 3.0

16. Lifespan Development: A Psychological Perspective (page 60) by Martha Lally and Suzanne Valentine-French is licensed under CC BY-NC-SA 3.0

20. Lifespan Development: A Psychological Perspective (page 61) by Martha Lally and Suzanne Valentine-French is licensed under CC BY-NC-SA 3.0

American College of Obstetricians and Gynecologists (ACOG). (2020). Your pregnancy and childbirth: Month to month (7th ed.). American College of Obstetricians and Gynecologists.

American College of Obstetricians and Gynecologists. (2020a). Obstetric care consensus: Approaches to limit unnecessary cesarean deliveries. Obstetrics & Gynecology, 135(6), e114-e120. https://doi.org/10.1097/AOG.0000000000003782

Davis-Floyd, R. E. (2003). Birth as an American rite of passage. University of California Press.

Grotevant, H. D. (2011). Family processes and the development of children’s identities. In D. L. Peterson & R. J. Rainer (Eds.), Handbook of family development and intervention (pp. 509-527). John Wiley & Sons.

Kleinman, A., & Benson, P. (2006). Anthropology in the clinic: The problem of cultural competency and how to fix it. PLoS Med, 3(10), e294.

Low, L. K., & Moffat, A. (2020). Managing pain in childbirth: The role of individual differences and perception. Journal of Perinatal Education, 29(3), 125-134. https://doi.org/10.1891/JPE-20-0025

Rothman, B. K. (2003). The educated childbirth: Technology, choice, and the changing nature of birth. In J. M. Leavitt & L. R. Shapiro (Eds.), The Social Medicine Reader: Volume 1 - Patients, doctors, and illness (pp. 231-246). Duke University Press.