on prenatal development that are examples of microsystem, mesosystem, exosystem, and macrosystem, factors.
2 Suppose you were creating a program to support pregnant women and their families in delivering healthy babies. Identify factors that you might address at each level of Bronfenbrenner’s model. Discuss your program and how it may help promote healthy infants.
3 What specific advice would you provide to a pregnant woman to help her promote a healthy pregnancy?
Childbirth
Thirty-eight weeks after conception (or 40 weeks after the last menstruation), childbirth (also known as labor) begins.
Labor
Labor progresses in three stages. The first stage of labor, dilation, is the longest. It typically lasts 8 to 14 hours for a woman having her first child; for later-born children, the average is 3 to 8 hours. Labor begins when the mother experiences regular uterine contractions spaced at 10- to 15-minute intervals. Initial contractions may feel like a backache or menstrual cramps or may be extremely sharp. The amniotic sac, a membrane containing the fetus surrounded by fluid, may rupture at any time during this stage, often referred to as the “water breaking.” The contractions, which gradually become stronger and closer together, cause the cervix to dilate so that the fetus’s head can pass through, as shown in Figure 3.9.
The second stage of labor, delivery, begins when the cervix is fully dilated to 10 centimeters and the fetus’s head is positioned at the opening of the cervix—known as “crowning.” It ends when the baby emerges completely from the mother’s body. It is during this stage that the mother typically feels an urge to push or bear down with each contraction to assist the birth process. Delivery can take from 30 minutes to an hour and a half.
Figure 3.9 Stages of Labor
Source: Adapted from Tortora and Derrickson (2009).
In the third stage of labor, the placenta separates from the uterine wall and is expelled by uterine contractions. This typically happens about 5 to 15 minutes after the baby has emerged, and the process can take up to a half hour.
The newborn emerges during the second stage of labor.
©iStockphoto.com/delectus
Medication During Delivery
Medication is administered in over 80% of births in the United States (Declercq, Sakala, Corry, Applebaum, & Herrlich, 2014). Several drugs are used during labor, with varying effects. Analgesics, such as tranquilizers, reduce the perception of pain. They may be used in small doses to relieve pain and to help the mother relax. However, these drugs pass through the placenta to the fetus and are associated with decreases in heart rate and respiration (Hacker, Gambone, & Hobel, 2016). Newborns exposed to some medications show signs of sedation and difficulty regulating their temperature (Gabbe et al., 2016). Anesthetics are painkillers that block overall sensations or feelings. General anesthesia (getting “knocked out”) blocks consciousness entirely; it is no longer used because it is transmitted to the fetus and can slow labor and harm the fetus.
Today, the most common anesthetic is an epidural, in which a pain-relieving drug is administered to a small space between the vertebrae of the lower spine, numbing the woman’s lower body. There are several types of epidurals, with varying numbing effects ranging from immobilizing the lower body to numbing only the pelvic region, enabling the mother to move about (a so-called walking epidural). Epidurals, however, are associated with a longer delivery, as they weaken uterine contractions and may increase the risk of a cesarean section, as discussed next (Gabbe et al., 2016; Herrera-Gómez et al., 2017). An analysis of nearly 15,500 deliveries suggested that newborns exposed to epidural anesthesia did not differ from those exposed to no anesthesia (Q. Wang et al., 2018). The American College of Obstetricians and Gynecologists (2017) has concluded that the proper administration of medication poses few risks to the newborn and pain medication should be available to all women.
Cesarean Delivery
Sometimes a vaginal birth is not possible because of concerns for the health or safety of the mother or fetus. For example, normally the baby’s head is the first part of the body to exit the vagina. A baby facing feet-first is said to be in a breech position, which poses risks to the health of the baby. Sometimes the obstetrician can turn the baby so that it is head-first. In other cases, a cesarean section, or C-section, is common. A cesarean section is a surgical procedure that removes the fetus from the uterus through the abdomen. About 32% of U.S. births were by cesarean section in 2016 (J. A. Martin et al., 2018). Cesarean sections are performed when labor progresses too slowly, the fetus is in breech position or transverse position (crosswise in the uterus), the head is too large to pass through the pelvis, or the fetus or mother is in danger (Jha, Baliga, Kumar, Rangnekar, & Baliga, 2015; Visscher & Narendran, 2014). Babies delivered by cesarean section are exposed to more maternal medication and secrete lower levels of the stress hormones that occur with vaginal birth that are needed to facilitate respiration, enhance circulation of blood to the brain, and help the infant adapt to the world outside of the womb. Interactions between mothers and infants, however, are similar for infants delivered vaginally and by cesarean section (Durik, Hyde, & Clark, 2000).
Natural Childbirth
Natural childbirth is an approach to birth that reduces pain through the use of breathing and relaxation exercises. Natural childbirth methods emphasize preparation by educating mothers and their partners about childbirth, helping them to reduce their fear, and teaching them pain management techniques. Although most women use at least some medication in childbirth, many women adopt some natural childbirth methods.
The most widely known natural childbirth method—the Lamaze method—was created by a French obstetrician, Ferdinand Lamaze (1956). The Lamaze method entails teaching pregnant women about their bodies, including detailed anatomical information, with the intent of reducing anxiety and fear. When women know what to expect and learn a breathing technique to help them relax, they are better able to manage the pain of childbirth. The Lamaze method relies on the spouse or partner as coach, providing physical and emotional support and reminding the mother to use the breathing techniques.
In addition to the expectant mother’s partner, a doula can be an important source of support. A doula is a caregiver who provides support to an expectant mother and her partner throughout the birth process (Kang, 2014). Doulas provide education about anatomy, delivery, and pain management practices, such as breathing. The doula is present during birth, whether at a hospital or other setting, and helps the woman carry out her birth plans. The presence of a doula is associated with less pain medication, fewer cesarean deliveries, and higher rates of satisfaction in new mothers (Gabbe et al., 2016; Kozhimannil et al., 2016).
Home Birth
Although common in nonindustrialized nations, home birth is rare, comprising 1.5% of all births in 2016 in the United States (MacDorman & Declercq, 2016). The remaining 98% of births occur in hospitals. Most home births are managed by a midwife, a health care professional, usually a nurse, who specializes in childbirth. Midwives provide health care throughout pregnancy and supervise home births. One review of 50 studies found that the use of midwives, whether as part of a home birthing plan or as part of a plan to birth in a hospital setting, is associated with reduced neonatal mortality, reduced preterm birth, fewer interventions, and more efficient use of medical resources (Renfrew et al., 2014).
Is a home birth safe? A healthy woman, who has received prenatal