Anatomy of Childbirth
When a mother brings a baby into the world, it should always
be a joyous occasion. In developed nations like the United
States, it usually is. But in developing countries,
particularly in poor villages far from proper medical care,
childbirth can be fraught with life-threatening hazards. The
World Health Organization estimates that roughly 529,000 women
die each year from problems related to childbirth, and the
number of babies that are stillborn is even higher. In this
feature, follow the stages of normal labor and delivery, and
learn about potential problems that can arise as well as
treatments used to cope with them.—Rima Chaddha
Note: This feature is not meant to be comprehensive. For more
complete details on the birthing process, please see the
National Institute of Health's
MedlinePlus: Childbirth.
Stage 1: Active labor
Duration: Usually up to 10 hours
The process
Under normal conditions, a mother is pregnant for about 38
weeks before entering labor, the process of delivering her
baby. As labor begins, the mother's body produces large
quantities of the hormone oxytocin, which causes the muscles
in her uterus to contract. When contractions are about five
minutes apart and the cervix, the baby's passageway out of the
uterus, has opened to a diameter of about four centimeters
(1.5 inches), the mother has entered what doctors call "active
labor." During this stage, the cervix gradually becomes
shorter as it continues to open. Eventually, it dilates to
around 10 centimeters (four inches), which is when the baby's
head begins its descent from the uterus.
Some risks
In some cases, labor can slow down or even stop completely,
especially if the mother is delivering her first child. In the
developing world, where access to adequate medical care is
often limited, women can sometimes be in labor for days. If
there is an obstruction—if the baby is too large to
descend through the pelvis or if the mother's cervix does not
open all the way, for example—the baby's head can place
so much pressure on the uterine wall bordering the bladder or
rectum that blood cannot get to that tissue. If it lasts long
enough, this pressure can cause the tissue to die and small
holes called fistulas to form. About 9,000 women develop
fistulas each year in Ethiopia alone.
Treatment options
If labor is not progressing normally, doctors or midwives may
intervene to augment or induce labor, sometimes by giving the
mother intravenous synthetic oxytocin or by applying a
hormonal gel directly to the cervix to encourage it to open.
Usually the mother's "water" has already broken—that is,
the amniotic sac of fluid surrounding the baby has ruptured.
But if it hasn't, the caregivers may puncture the sac manually
to help the labor progress. In secluded parts of the
developing world, such treatments are often not available, nor
is the relatively straightforward surgery needed to correct
fistulas, which could result from inadequate medical care.
(See "Second Chances" for more on fistula surgery and its enormous benefits.)
Stage 2: Delivery
Duration: 20 minutes to 2 hours
The process
Stage Two begins when the cervix is fully dilated and ends
with the delivery of the baby. At the beginning of this stage,
also called the "pushing stage," the baby's head moves through
the opening of the pelvis. By complying with the natural urge
to push, the mother helps the infant into the world. But if
the mother does not experience the need to push, a possible
result of having received an epidural, an injection of
anesthetic to help ease the discomfort of labor, doctors or
nurses will coach her through this process.
Some risks
In developing nations, where many women are physically small
from malnourishment yet whose full-term fetuses may be of
normal size, vaginal birth can sometimes prove all but
impossible. Without the option of cesarean (surgical) birth, a
too-small pelvis is likely to result in infant and sometimes
maternal death. Other risks to the infant during both labor
and delivery can include the early detachment of the placenta
or damage to the umbilical cord, which together supply the
fetus with its oxygen and nutrients.
Treatment options
Even in developed nations, where nutrition is typically
adequate, some women possess smaller-than-average pelvises.
When the fetus is too large to be delivered vaginally, doctors
will perform a cesarean section to surgically remove the
infant from the womb. Cesareans may also be performed if other
complications arise to make vaginal birth too risky.
Tragically, such emergency surgery is often not an option in
remote villages in the developing world.
Stage 3: Post-delivery
Duration: 10-30 minutes
The process
Typically within 15 minutes of the baby's delivery and after
doctors have cut the umbilical cord, the placenta is expelled
from the uterus, usually after a few more pushes from the
mother. Since the placenta developed during pregnancy
specifically to deliver nutrients and oxygen to the baby, the
mother no longer needs it.
Some risks
During childbirth, mothers usually lose less than 20 ounces of
blood, but women lacking proper medical care will often lose
far more. In fact, postpartum hemorrhage, or excessive
bleeding after delivery, is the leading cause of maternal
death in developing countries. The second leading cause is
sepsis, or an infection of the blood, which can occur at any
time during delivery. Altogether, one in every 2,500 mothers
worldwide dies each year of childbirth-related causes. (The
developed world sees far fewer deaths; that figure in the
United States, for instance, is one in every 10,000 mothers.)
Treatment options
Studies have found that the hormone oxytocin can aid in
preventing postpartum hemorrhaging. While women produce the
chemical naturally, doctors will sometimes administer
synthetic oxytocin as needed. Breastfeeding also triggers the
release of oxytocin—the chemical is associated with
bonding in humans, which helps explain the particularly strong
bond between mothers and their children. Cases of sepsis are
rare in developed nations, where sanitary conditions in
hospitals have greatly improved over the past century. When an
infection does occur, a dosage of antibiotics can help fight
it.
