How Childbirth Works

­Other than buying up supplies, staying healthy and going to the doctor regularly, there's not much for a pregnant woman to do but wait until the big day rolls around, right? Wrong. There are many decisions to be made and options to consider. That's why pregnant women often write a birth plan, a wish list for their ideal birth. There's no way to know ahead of time what might be medically necessary, but a birth plan is a way for her to express her preferences.

These preferences begin with the atmosphere in which she labors and delivers. Perhaps she'd rather have only necessary personnel in the room (no medical students or residents, for example), or she'd like the freedom to eat and drink while in early labor. Some doctors stress the importance of only having clear fluids or ice chips due to the possibility of anesthesia or surgery, but others have relaxed these rules. A woman in labor can also choose not to have her heart rate monitored and say no to an internal fetal monitor (which involves screwing an electrode directly into the fetus's scalp) unless doctors are concerned about the fetus's heart rate.

Most pregnant women feel strongly about pain relief during the childbirth process. Some would prefer to avoid medication, while others don't see anything wrong with taking drugs to help ease the pain. In a birth plan, women can indicate when they would like to be offered medication (as soon as possible or not until they ask for it) and what kind: an IV narcotic such as Stadol or an epidural. Some women also prefer nonmedical pain relief options, such as massages or warm showers or baths.

It's important for a woman to express her desire to deliver without intervention (including induction, forceps, vacuums or Cesarean) if that's what she prefers. There's also the issue of the episiotomy. This is when a doctor makes an incision in the perineum, the area between the vagina and the anus, to allow for a wider vaginal opening and a smoother delivery. After delivery, the perineum is stitched closed. Some women would prefer to have the tissue tear by itself (which sometimes happens) or try massages or warm compresses to try to stretch the area before resorting to an episiotomy. Critics claim that doctors are too quick to cut this sensitive area. It usually takes several weeks to heal following one, and some women have lasting pain during sexual intercourse afterwards.

Once the baby actually arrives, there are still many options. Perhaps the mother would prefer to have her partner cut the cord and have the baby laid on her chest immediately. Some don't care about who cuts the cord and would rather have the baby after he or she is cleaned and weighed. The mother can also refuse or delay some routine tests and treatments, or request that the baby stay in her room instead of being in the nursery. Some mothers who are breastfeeding prefer that their baby not be given bottles or pacifiers to avoid confusion, too.

But before we get to all of this in more detail, let's start with two very important decisions: who will deliver the baby, and where it will take place.

For some women, who will deliver the baby and where it will take place are simple decisions. They already have an obstetrician/gynecologist (OB/GYN) who will deliver their baby in a hospital where the doctor has privileges.

Sometimes women who want a natural childbirth find that midwives are more open to a less invasive approach. Often, midwives work in conjunction with doctors, who can step in if there are complications.

An additional option is to employ a doula as well as a doctor or midwife. A doula isn't a medical professional, but she assists with the physical, informational and emotional needs of both the pregnant woman and her partner. She may provide massages during labor, advocate for the pregnant woman in speaking with medical professionals, and assist with tasks after the birth such as caring for the baby or cooking.

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­If a woman decides to give birth at a traditional hospital with any or all of the people listed above, she still has plenty of options. Typically, she would be moved from room to room during the labor, delivery and recovery stages, and then to another room (either semiprivate or private) after the baby is born. However, some hospitals have birthing rooms available in which all stages of the process take place. Often the birthing rooms are more comfortable for her partner and other people who may be attending the birth; they feel more like bedrooms than hospital rooms.

Some women choose to deliver at a birthing center, most often when their pregnancy is considered low risk. Birthing centers are usually staffed by nurses and midwives rather than doctors, although there's a doctor available for emergencies. Sometimes they're attached to hospitals, but they can also be freestanding. Generally, birthing center staff won't induce labor, provide medical pain relief or perform other typical medical interventions during the labor and delivery process. Some people consider them a compromise between a hospital birth and a home birth.

So what is a home birth like? On the next page, we'll find out -- and look at some other options, such as water births.

More and more women are choosing to give birth at home. Proponents argue that childbirth isn't a medical procedure, but a natural experience that may require medical intervention. Home births are typically attended by midwives, who may bring equipment such as oxygen for the baby or IVs to provide fluid for the mother if necessary. Many medical professionals agree that women who have low-risk pregnancies can do well giving birth at home with a midwife present, who will advise if moving to the hospital is necessary. However, the American Medical Association is currently lobbying to outlaw home births, claiming that the safest place for childbirth is in a hospital or a birthing center that adheres to strict guidelines. The American College of Obstetricians and Gynecologists has officially opposed home births since the mid-1970s.

At the other end of the spectrum are unassisted home births or "free births." This means that the woman gives birth at home without any medical professional present, just friends and family. Advocates claim that this is most natural way to give birth, and women who choose this option have often had bad hospital birth experiences in the past. Most medical professionals, however, claim that it's irresponsible and dangerous. If something goes wrong, the consequences can be deadly. While the majority of women who choose unassisted births continue to see a doctor or midwife for prenatal care and may purchase equipment or take classes to learn medical procedures, some don't.

An alternative to giving birth lying on your back in a bed is to have a water birth, which is usually only available at a birthing center or a home birth. It simply means that the woman labors in a tub or pool of warm water. The warmth and buoyancy can help the mother get more comfortable. Some women labor in the tub but get out for delivery, while others deliver the baby underwater. They believe that this is a more soothing way to come into the world -- going from one watery place to another. Because the baby doesn't begin breathing until exposed to air and receives oxygen through the ­umbilical cord until it's cut, there's minimal risk.

Leboyer Gentle Birth is a way of giving birth that has become popular in some countries (although the United States isn't yet one of them). The birthing room should be calm and quiet, with dimmed lights and gentle music. After the baby is delivered, he or she spends a longer amount of time lying on the mother's stomach before having the cord cut. The baby is then placed into a bath of warm water to simulate the comforting feelings of the womb.

Now that you know some options for giving birth, let's take a look at childbirth classes and methods. 

Women can get through the experience of labor and delivery just fine without any classes or much preparation; there is an element of the body doing what comes naturally. However, many women believe that learning specific methods can make the process easier, especially if they're interested in having a natural childbirth. Typically, an instructor explains everything from prenatal care and fetal development to the benefits of breastfeeding and how to take care of a baby. But when most people hear "childbirth classes," they don't think so much about the information aspect. Instead, they probably think about women huffing and puffing while in labor.

Lamaze is probably the best known of these methods. Named after the French doctor who introduced it in the early 1950s, this method aims to provide women with ways to relax and deal with pain during a natural childbirth. One way is through patterned breathing, or cycling between deep and shallow breaths. When in pain, people often tend hold their breath or hyperventilate, which can actually make things more painful. It also uses up a lot of energy that should be conserved for when it's time to push. Lamaze instructors teach women to focus on breathing through their contractions. They also advocate having a focal point in the room while laboring. Classes are normally taken with a birth coach, who might be a partner, friend or relative. Instructors teach them how best to support the expectant mother -- through massage techniques, for example.

The Bradley method hasn't been around quite as long as Lamaze, but it became more popular when Dr. Bradley pushed a book in 1996 titled "The Husband-Coached Childbirth." Like Lamaze, Bradley emphasizes education and preparation. It also advocates for a birth coach, with the belief that most women can give birth without needing medical intervention. The difference is that this method places more emphasis on muscle control. People in pain tend to tense muscles, which can make the pain worse. Bradley instructors teach how tightening and relaxing different muscle groups in the body can make the expectant mother relax.

One method isn't necessarily better than the other; there are women who have sworn by both. Some childbirth classes teach elements of both methods. Using a method like Lamaze or Bradley doesn't mean a pregnant woman can't also receive drugs. Some women use the method up until the point where they receive an ­epidural. Even if the methods learned in childbirth classes don't help to relieve pain, the information that can be gained by the women and their partners can be invaluable.

OK, so you know where you want to give birth, how you want to do it, and who's going to be assisting you. Now what? 

Most women expect that it'll be obvious to them when they go into labor, but if it's their first baby, they may not be so sure. The most obvious signs are contractions. Labor contractions should be strong enough so that it's difficult do anything else, and they last about a minute. They're usually in the lower back and pelvis and feel similar to menstrual cramps. Labor contractions also fall into a pattern, which is why it's important to time them. Once they've been coming every three to five minutes for about an hour (for a first baby), then it's usually time to get going. As time goes on, they get stronger, last longer and get closer together.

The dramatic breaking of the amniotic sac, which is what people are referring to when they say a woman's water broke, means that a woman is definitely in labor.

Sometimes weeks before she goes into labor, a woman's cervix begins to open, or dilate. It must dilate to 10 centimeters for a vaginal delivery. The cervix also gets thinner, known as effacement. Neither dilation nor effacement is felt by the woman as they're happening, but doctors and midwives check for these signs during exams. She may notice the loss of her mucus plug as her cervix effaces and dilates, which is also known as bloody show because it appears as a brown, sometimes bloody discharge.

While all of this is going on, the baby is supposed to drop down into the pelvis, known as lightening, which usually happens a few weeks before labor begins. This takes pressure off the mother's stomach and lungs but can put more on her bladder. The baby should be head-down in the classic birth position. He or she is probably not moving as much, because there's not a lot of wiggle room. The mother may feel little jumps that are actually the baby's hiccups as he or she practices breathing and inhales amniotic fluid. In addition to all this, the baby is building up meconium (the first fetal bowel movement), which will be passed a couple of days after birth.

­A woman's due date is generally calculated as 280 days (40 weeks) after the first day of her last missed period. If you do the math, that would make pregnancy 10 months long, not nine. However, most months aren't four calendar weeks long; they're usually four weeks plus a few days, which accounts for the extra time. It's just simpler to say nine months because the pregnancy is divided into trimesters, or three-month periods. To further complicate matters, although a pregnancy is considered full term at 40 weeks, the due date is an estimation. Women generally give birth anywhere from week 38 to week 42.

A baby born before week 38 is considered premature, but most doctors will allow delivery at week 35 provided the baby's lungs are mature. If the mother goes into labor before this point, doctors may initially try to stop it by prescribing bed rest and IV fluids. If the cervix isn't dilated more than 3 centimeters or effaced, the next step is to administer drugs through the IV such as Yutopar or magnesium sulfate to delay labor. Rarely do these interventions bring the pregnancy to full term, but any extra time is helpful in giving the baby the best chance of survival. If it's before week 34, doctors may give the mother ­steroids to speed the development of the baby's lungs.

On the next page, we'll take a look at the early stages of labor -- and options for pain relief. 

The first stage of labor is known as early labor. It can last up to eight hours while the cervix continues to dilate and efface. Contractions during this stage are generally mild and sometimes described as coming in waves. They can be as long as 20 minutes apart or as few as five minutes apart. During this phase, the mother usually eats, sleeps, moves around and does whatever she likes while waiting for labor to progress. Many women know that they've progressed into the next stage, active labor, because they can't sleep through the contractions.

Contractions during active labor are more intense and painful; they also occur every couple of minutes. This is usually the time when pain relief comes into play.

­If medical pain relief is a part of her birth plan, a woman has a couple of options. A common one is a form of nerve block called an epidural. An anesthesiologist inserts a needle between two vertebrae and then threads in a tube and tapes it down onto the woman's back. An anesthetic, such as lidocaine, enters the cerebrospinal fluid and essentially numbs the body from the breasts downward, and most women feel relief within 20 minutes. They'll have to use a bedpan or be catheterized to urinate, since walking isn't possible.

There's also the option of a walking epidural, or combined spinal epidural (CPE). This uses smaller amounts of the anesthetic used in regular epidurals, along with a narcotic such as morphine. It only numbs the abdominal muscles and works within a few minutes. Some women who have a CPE can walk -- other times, their muscles are too weak or the doctor would prefer that they didn't.

Both types of epidurals have side effects. Sometimes the dura mater, the tough membrane surrounding the spinal cord, is punctured, causing a headache. Sometimes epidurals cause the labor to slow down and labor must be speeded up again using Pitocin.

In addition to nerve blocks, women can have analgesics -- pain relievers -- such as Demerol administered through an IV. Sometimes these have an effect on the baby; it may be drowsy and initially have trouble breathing upon birth. The risk of lasting effects is minimal.

Depending on the options available, laboring women may choose alternative methods of pain relief. Changing positions, kneeling, walking or rocking in a chair can help, as can standing or sitting in a warm shower. Massages, acupressure and acupuncture from a partner or doula might also soothe pain.

During active labor, the cervix generally dilates about 1 centimeter an hour. When contractions become the most intense, they may be only 30 seconds apart. During the transition phase, the cervix fully dilates. Active labor usually lasts three to six hours, and the transition phase about an hour. Delivery is imminent, and without drugs to relieve the pain (which can still be asked for and administered during this phase), the woman may have a chaotic mix of sensations and feelings. Women who have had epidurals are usually calmer because of the loss of sensation. Those who are going for a nonmedicated childbirth may feel sick, have chills and shake (which can also happen with an epidural). The urge to push becomes overwhelming.

But it doesn't always happen this way. Before we get to delivery, let's take a look at some complications that can occur during the stages of labor.

­There are many potential complications during labor and delivery, but let's start with the progression of labor itself. In the last section, we looked at how labor is supposed to progress. But what if the expectant mother's body just isn't following those guidelines? Sometimes, the bag of water breaks but she doesn't have any contractions. Once the seal is broken, so to speak, the baby is open to infection, so labor has to be induced. Conditions such as toxemia and gestational diabetes may also warrant an induction to protect the health of both the mother and the baby.

Labor might also be induced when the woman is past her due date, because doctors want to prevent postmaturity of the placenta. Essentially, the placenta starts to wear out after 41 or 42 weeks of feeding the baby. A post-due date baby might also have his or her first bowel movement in the womb and inhale it, which can cause breathing problems because the meconium is sticky and tarlike.

Doctors may use one of three methods to bring on labor. If the amniotic sac hasn't yet broken, a hooked tool called an amniohook can break it manually. Sometimes this is enough to start the process, and the woman is placed on an IV drip containing Pitocin. This drug is just an artificial version of oxytocin, the hormone that causes contractions. Pitocin drips are also used if the sac has ruptured but labor hasn't progressed rapidly enough, or if the baby is starting to show signs of mild distress. Some women report stronger, more painful contractions when their labor is induced with Pitocin. Another method is the use of prostaglandin gel. This gel is applied to the cervix to help it dilate and simulate labor. It can take up to 12 hours for labor to begin.

Just as with pain relief, there are also natural methods used to induce labor. Sexual intercourse is a popular one. Sometimes the movement is enough to get things going. In addition, the man's semen contains prostaglandin, the same hormone applied in gel form to the cervix to induce labor. Certain foods, such as spicy food, Chinese or Italian have also been credited with inducing labor, but there's no real evidence to support it.

Midwives may also administer herbs such as black cohosh or goldenseal to induce or strengthen contractions, but these should only be used by someone who is knowledgeable and skilled in their use. There are also pressure points on the body that practitioners of acupressure and acupuncture can stimulate in an attempt to induce birth. Rubbing the nipples is known to stimulate release of oxytocin, so this can also induce labor.

 

­Sometimes things don't progress as they should. Maybe the doctor feels the baby's head is too big to fit through the vaginal opening. The baby may not be moving down into the birth canal or isn't in the right position. Vaginal deliveries are usually possible with a breech position in which the baby's buttocks are pointed downward instead of his head, but sometimes the baby is lying horizontally. Most medical professionals don't like to turn the baby manually because it can trigger premature labor; babies in these positions in the weeks leading up to the due date often move into position by themselves. But if not, then a Cesarean or C-section becomes the only way to get him out safely. (Read How C-sections Work for the full story.)

The baby's heart rate becoming erratic or slowing down indicates fetal distress. This can be caused by a number of things, including having the umbilical cord wrapped around the neck, which means that the baby isn't receiving enough oxygen and must be delivered as soon as possible. The birth plan usually goes out the window at this point because a life is in danger. Often this means a C-section. If the woman has had an epidural, it can be turned up and provide enough nerve blockage for pain relief. If not, an anesthesiologist can administer one or she may be put under general anesthesia if there's not enough time.

If the situation doesn't warrant a Cesarean section, other methods can be used to extract the baby. An episiotomy is one way. Forceps, which look like tongs, were once also commonly used to guide the baby out of the birth canal when it appeared that he or she wouldn't fit through otherwise, but they occasionally caused injury to the baby's soft skull. Today they're rarely used -- doctors are more likely to use a vacuum or order a Cesarean. Vacuums (which look like small suction cups with plungers that attach to the baby's scalp) are often used when the baby is slightly higher in the birth canal. The risk of injury is lower than with forceps, although the baby may have a swollen spot on its head for a little while as a result. Episiotomies were often done in conjunction with forceps deliveries, but they aren't usually necessary with vacuum extractions.

These are examples of what can go wrong, but many times, things go exactly like they're supposed to. Let's take a look at what happens when it's time to push. 

When the cervix is completely dilated to 10 centimeters and effaced, it's finally time to push.

­This stage of labor can last anywhere from a few minutes to a few hours -- it usually gets shorter with each child because the vaginal canal has gotten more flexible over time. The mother bears down as if she's pushing out a bowel movement and holds it for a count of 10 before releasing. The pushing stage is pretty intense -- she may break a sweat and breathe heavily.

During the course of labor and delivery, women and their partners should expect to see things like blood, mucus and amniotic fluid. But those aren't the only fluids to expect. Drugs and strong contractions can cause laboring women to lose control of their bladders if they haven't been catheterized. Some drugs can also cause women to feel nauseated and vomit. It's common for women to push out some feces when pushing out the baby.

As the baby begins to crown (which is when the head shows at the vaginal opening), the spaces between episodes of pushing become shorter. This is the time that an episiotomy may be performed or the doctor may use a vacuum or forceps if the baby's head seems to be getting stuck. Usually, a few very big pushes are enough to release the head, and the rest of the body tends to follow pretty easily. Getting the head through is the most painful part; some women say that the burning and tearing makes them feel as if they might rip open, but the vagina is very elastic.

If the woman has had an epidural, she shouldn't have much pain, just pressure. Usually the epidural is turned down or off so that she can better feel her contractions. Sometimes the doctor must tell her when to push by monitoring her contractions because she can't feel them well enough. In this case the pushing isn't as effective as it would be if she could still feel everything, but women with epidurals deliver vaginally without intervention all the time. There's an increased risk of needing a vacuum or forceps, however.

The head's out! That's the hard part. Now what?

Once the head emerges, the doctor may pause to suction amniotic fluid from the baby's nose and mouth before helping the rest of the body to emerge. There are still some mild contractions, but then the placenta is usually delivered with a few pushes. The uterus continues to contract for a few minutes to help seal blood vessels. The placenta is examined within a day or two of delivery to check for abnormalities and find out what went wrong if there were problems during the pregnancy. It's usually discarded afterwards, but some people have other uses for the placenta. (See Should you save your baby's umbilical cord blood? for more information.)

Gone are the days when babies were held upside down and smacked on the bottom after emerging from the womb. Now they're normally laid on the stomach or chest of the mother while the umbilical cord is clamped and cut. What happens next depends on whether the mother has expressed preferences in a birth plan and the hospital's or birthing center's procedures. Typically, he or she is cleaned, given a battery of health tests and medications, weighed and measured. The mother may choose to refuse or delay some or all of these things, or request that her partner or someone else be present for them. Refusing some, like the application of silver nitrate or antibiotics to the baby's eyes to prevent infections, require the mother to sign a waiver first.

Some mothers want the baby to stay in their room instead of a nursery, or only sleep in the nursery at night. Not all hospitals will allow this, but there can be a partner or spouse present at all times in the nursery. Breastfeeding mothers may also specify that no bottles or pacifiers be given to the baby (which can make it harder for the baby to learn how to breastfeed, called nipple confusion).

The most important thing is to be educated about the hospital's or birthing center's practices and for the mother to figure out exactly what she wants. This can mean the difference between a happy childbirth experience and a disappointing one.

For even more information about pregnancy, babies and childbirth, click on the links on the next page.