Early labor prepares the body for delivery. This is a period of hours or days when the uterus regularly contracts and the cervix gradually thins out (called effacing) and opens (called dilation) to allow the baby to pass through.

Labor and delivery describe the process of childbirth. With regular contractions of the uterus and changes of the cervix (the opening of the uterus), a woman’s body prepares for childbirth, the baby is born, and the placenta follows.

NICHD research addresses many aspects of labor and delivery: the basic biology of labor and delivery; the efficacy, safety, and health outcomes of childbirth practices; and prevention and management of complications related to labor and delivery.

Preterm labor and delivery, also called premature labor and birth, share many features with regular labor and delivery. But they also have specific features all their own. For this reason, preterm labor and birth are addressed in a separate topic.

Common Name

Labor and delivery
Childbirth

Medical or Scientific Name

Labor and delivery

What are labor and delivery?

Labor and delivery are the process by which a baby is born.

Once the cervix has opened completely, pushing begins. If the baby and placenta come out through the vagina, this is known as a vaginal delivery.

When does labor usually start?

The due date is 40 weeks after the first day of the last menstrual period, although sometimes it is determined by an ultrasound. For most women, labor occurs sometime between week 37 and week 42 of pregnancy. Labor that occurs before 37 weeks of pregnancy is considered premature, or preterm labor. Labor that occurs at 37 or 38 weeks is now considered early term because babies born at that gestational age are still immature.

Just as pregnancy is different for every woman, the start of labor, the signs of labor, and the length of time it takes to go through labor will vary from woman to woman and even from pregnancy to pregnancy.

Signs of Labor

Some signs that labor may be close (although, in fact, it still might be weeks away) can include¹:

“Lightening.” This term describes when the fetus “drops,” or moves lower in the uterus. Not all fetuses drop before birth. Lightening gets its name from the feeling of lightness or relief that some women experience when the fetus moves away from the rib cage to the pelvic area. This allows some women to breathe easier and more deeply and to get relief from heartburn.
Increase in vaginal discharge. Called “show” or “the bloody show,” the discharge can be clear, pink, or slightly bloody. This occurs as the cervix begins to open (dilate) and can happen several days before labor or just as labor begins.

If a woman experiences any of the following signs of labor at any point in pregnancy, she should contact her health care provider:

Contractions every 10 minutes or more often
Change in color of vaginal discharge
Pain or pressure around the front of the pelvis or the rectum
Low, dull backache
Vaginal spotting or bleeding
Abdominal cramps, with or without diarrhea

Sometimes, if the health of the mother or the fetus is at risk, a woman’s health care provider will recommend inducing labor, using medically supervised methods, such as medication, to bring on labor.

Unless earlier delivery is medically necessary, waiting until at least 39 weeks before delivering gives mother and baby the best chance for healthy outcomes. During the last few weeks of pregnancy, the fetus’s lungs, brain, and liver are still developing.

The Is It Worth It? Initiative, from the NICHD’s National Child and Maternal Health Education Program, focuses on raising awareness of the importance of waiting until at least 39 weeks to deliver a baby, unless it is medically necessary to deliver earlier.

What are the stages of labor?

To view the original video, click Stages of Labor

Video Text Alternative: Stages of Labor

Video/Graphics	Audio
TITLE SLIDE: Stages of Labor Logo of the Eunice Kennedy Shriver National Institute of Child Health and Human Development
GRAPHIC SLIDE: Stage 1 Early Phase Computer-generated diagram of a fetus in the womb. The vagina and uterus are labeled with text, followed by a label pointing to the cervix reading “Cervix softens and thins.”	Narrator: Labor has three stages. In the first stage of labor, the body prepares to give birth. There are two phases: early and active. Early labor can last from hours to days. First-time moms may spend more time in this phase. The cervix, or the opening to the uterus, begins to soften; efface, or thin out; and dilate, or open. The cervical changes are necessary so the baby can pass through. Usually a woman’s water breaks during the first stage of labor. Contractions—or tightening of the uterus—become strong and regular. Typically, the woman will have a 30- to 70-second long contraction every 5 to 20 minutes. There may also be a stringy, bloody discharge from the vagina, called “bloody show.” This is considered normal.
GRAPHIC SLIDE: Stage 1 Active Phase A similar diagram as in the previous slide, but with the fetus turned slightly and pressed against the dilating cervix. The vagina and uterus are labeled with text, followed by a label pointing to the cervix reading “Dilated cervix.”	Narrator: Active labor occurs when the cervix starts to dilate more quickly. Contractions get stronger, last longer, and occur more often. The cervix continues to open wider, to about 10 centimeters. Then, pushing can start.
GRAPHIC SLIDE: Stage 2 A similar diagram as in the previous slide, but with the baby’s head past the cervix and crowning. The vagina, uterus, and umbilical cord are labeled with text, followed by a label pointing to the baby’s head reading “Infant’s head crowning.”	Narrator: In the second stage of labor, the child is born. A health care provider usually encourages the woman to “push” to help the baby move down the vagina. She might push for minutes or hours. Once the baby’s head starts to come out—called crowning—a provider guides the rest of the baby out. Childbirth is finished when the baby is completely out of the vagina. The provider then cuts and clamps the umbilical cord, which connected mom and baby during pregnancy.
GRAPHIC SLIDE: Stage 3 A similar diagram as in the previous slide, but without the fetus. The cut umbilical cord sticks out of the vagina and is still connected to the placenta inside of the uterus. The vagina and cervix are labeled with text, followed by the placenta and umbilical cord.	Narrator: The last stage of labor involves delivery of the placenta, or afterbirth. During pregnancy, the placenta supplies food and oxygen to the fetus. Once the umbilical cord is cut, the placenta has to come out. Contractions typically begin 5 to 10 minutes after the baby’s birth. During this time, the placenta detaches from the uterus. A provider may encourage the woman to “push” just as she did to deliver the baby. After 5 to 30 minutes, the placenta comes completely out of the vagina. Then, the process is complete.

Last Updated Date: 08/22/2014
Last Reviewed Date: 08/22/2014

Stage 1

The first stage of labor happens in two phases: early labor and active labor.

During early labor:

The cervix starts to open or dilate.
Strong and regular contractions last 30 to 60 seconds and come every 5 to 20 minutes.
The woman may have a bloody show.

A woman may experience this phase for a few hours or days, especially if she is giving birth for the first time.

During active labor:

Contractions become stronger, longer, and more painful.
Contractions come closer together.
The woman may not have much time to relax between contractions.
The woman may feel pressure in her lower back.
The cervix fully dilates to 10 centimeters.

Stage 2

During this stage, the cervix is fully dilated and ready for delivery. The woman will begin to push (or is sometimes told to “bear down”) to allow the baby to move through the birth canal.

During stage 2:

The woman may feel pressure on her rectum as the baby’s head moves through the vagina.
She may feel the urge to push, as if having a bowel movement.
The baby’s head starts to show (called “crowning”).
The health care provider guides the baby out of the vagina.
Once the baby comes out, the health care provider cuts the umbilical cord, which connected mother and fetus during pregnancy.

This stage can last between 20 minutes and several hours. It usually lasts longer for first-time mothers.

Stage 3

During this stage, the placenta is delivered. The placenta is the organ that gave the fetus food and oxygen through the umbilical cord during the pregnancy.

During stage 3:

Contractions begin 5 to 10 minutes after the baby is delivered.
The woman may have chills or feel shaky.

It may take 5 to 30 minutes for the placenta to exit the vagina.

What are the options for pain relief during labor and delivery?

The amount of pain felt during labor and delivery is different for every woman. The level of pain can depend on many factors, including the size and position of the baby and the strength of contractions. Some women learn breathing and relaxation techniques to help them cope with the pain. These techniques can be used along with one or more pain-relieving drugs.

A woman should discuss the many aspects of labor with her health care provider well before labor begins to ensure that she understands all of the options, risks, and benefits of pain relief during labor and delivery. It might also be helpful to put all the decisions in writing to clarify the options chosen.

Types of Pain-Relieving Medications

Pain-relief drugs fall into two categories: analgesics (pronounced an-l-JEE-ziks) and anesthetics (pronounced an-uhs-THET-iks).

There are different forms of each.

Analgesics

Analgesics relieve pain without causing total loss of feeling or muscle movement. These drugs do not always stop pain completely, but they reduce it.

Systemic analgesics affect the whole nervous system rather than a single area. They ease pain but do not cause the patient to go to sleep. Systemic analgesics are often used in early labor. They are not given right before delivery because they may slow the baby’s breathing and reflexes. They are given in two ways:
- Injected into a muscle or vein
- Inhaled or breathed in with a mixture of oxygen. The woman holds a mask to her face, meaning she decides how much or how little analgesic is needed for pain relief.
Regional analgesics relieve pain in one region of the body. In the United States, regional analgesia is the most common way to relieve pain during labor. Several types of regional analgesia can be given during labor:
- Epidural analgesia, also called an epidural block or an epidural, causes loss of feeling in the lower body while the patient stays awake. The drug starts working about 10 to 20 minutes after it is given. A health care provider injects the drug near the spinal cord. A small tube (catheter) is placed through the needle. The needle is then withdrawn, but the tube stays in place. Small amounts of the drug can then be given through the catheter throughout labor without the need for another injection.
- A spinal block is an injection of a much smaller amount of the drug into the sac of spinal fluid around the spine. The drug starts working right away, but it only lasts for 1 to 2 hours. Usually a spinal block is given only once during labor, to help with pain during delivery.
- A combined spinal-epidural block, also called a “walking epidural,” gives the benefits of an epidural block and a spinal block. The spinal part relieves pain immediately. The epidural part allows drugs to be given throughout labor. Some women may be able to walk around after a combined spinal-epidural block.

Anesthetics

Anesthetics block all feeling, including pain.

General anesthesia causes the patient to go to sleep. The patient does not feel pain while asleep.
Local anesthesia removes all feeling, including pain, from a small part of the body while the patient stays awake. It does not lessen the pain of contractions. Health care providers often use it when performing an episiotomy (pronounced uh-pee-zee-OT-uh-mee), a surgical cut made in the region between the vagina and anus to widen the vaginal opening for delivery, or when repairing vaginal tears that happen during birth.

What is natural childbirth?

Natural childbirth can refer to many different ways of giving birth without using pain medication, either in the home or at the hospital or birthing center.

Natural Forms of Pain Relief

Women who choose natural childbirth can use a number of natural ways to ease pain. These include:

Emotional support
Relaxation techniques
A soothing atmosphere
Moving and changing positions frequently
Using a birthing ball
Using soothing phrases and mental images
Placing a heating pad or ice pack on the back or stomach
Massage
Taking a bath or shower
Hypnosis
Using soothing scents (aromatherapy)
Acupuncture or acupressure
Applying small doses of electrical stimulation to nerve fibers to activate the body’s own pain-relieving substances (called transcutaneous electrical nerve stimulation, or TENS)
Injecting sterile water into the lower back, which can relieve the intense discomfort and pain in the lower back known as back labor

What is a C-section?

A C-section, short for cesarean section, is also called cesarean birth. Cesarean birth is the delivery of a baby through surgical cuts in a woman’s abdomen and uterus. The uterus is then closed with stitches that later dissolve. Stitches or staples also close the skin on the belly.

According to the U.S. Centers for Disease Control and Prevention, in 2011, almost 33% of births were by cesarean delivery. According to the Agency for Healthcare Research and Quality, the number of cesarean deliveries increased by 72% between 1997 and 2008.

When is cesarean delivery needed?

Cesarean delivery may be necessary in the following circumstances:

A pregnancy with two or more fetuses (multiple pregnancy). A cesarean delivery may be needed if labor has started too early (preterm labor), if the fetuses are not in good positions in the uterus for natural delivery, or if there are other problems.
Labor is not progressing. Contractions may not open the cervix enough for the baby to move into the vagina.
The infant’s health is in danger. The umbilical cord, which connects the fetus to the uterus, may become pinched, or the fetus may have an abnormal heart rate. In these cases, a C-section allows the baby to be delivered quickly to address and resolve the baby’s health problems.
Problems with the placenta. Sometimes the placenta is not formed or working correctly, is in the wrong place in the uterus, or is implanted too deeply or firmly in the uterine wall. This can cause problems, such as depriving the fetus of needed oxygen and nutrients or vaginal bleeding.
The baby is too large. Women with gestational diabetes, especially if their blood sugar levels are not well controlled, are at increased risk for having large infants. And larger infants are at risk for complications during delivery. These include shoulder dystocia, when the infant’s head is delivered through the vagina but the shoulders are stuck.
The baby is breech, or in a breech presentation, meaning the baby is coming out feet first instead of head first.
The mother has an infection, such as HIV or herpes, that could be passed to the baby during vaginal birth. Cesarean delivery could help prevent transmission of the virus to the infant.
The mother has a medical condition. A C-section enables the health care provider to better manage the mother’s health issues.

Women who have a cesarean delivery may be given pain medication with an epidural block, a spinal block, or general anesthesia. An epidural block numbs the lower part of the body through an injection in the spine. A spinal block also numbs the lower part of the body but through an injection directly into the spinal fluid. Women who receive general anesthesia, often used for emergency cesarean deliveries, will not be awake during the surgery.

What are the risks of a C-section?

Cesarean birth is a type of surgery, meaning it has risks and possible complications for both mother and infant.

Possible risks from a C-section (which are also associated with vaginal birth) include:

Infection
Blood loss
Blood clots in the legs, pelvic organs, or lungs
Injury to surrounding structures, such as the bowel or bladder
Reaction to medication or anesthesia used

A woman who has a C-section also may have to stay in the hospital longer. The more C-sections a woman has, the greater her risk for certain medical problems and problems with future pregnancies, such as uterine rupture and problems with the placenta.

Can a C-section be requested?

Some women may want to have a cesarean birth even if vaginal delivery is an option. Women should discuss this option in detail with their health care provider before making a final decision about a C-section.

As is true for vaginal births, unless there is a medical necessity, delivery should not occur before 39 weeks of pregnancy (called full term). Watch this video to learn why it is important for the mother’s and infant’s health to wait until at least 39 weeks to deliver unless there is a medical reason to do so earlier.

What is induction of labor?

Labor induction is the use of medications or other methods to cause, or induce, labor. This practice is used to make contractions start.

When would a provider induce labor?

Induction is usually limited to situations when there is a problem with the pregnancy, or when a baby is overdue.

Several weeks before labor begins, the cervix begins to soften (called “ripening”), thin out, and open to prepare for delivery. If the cervix is not ready, especially if labor has not started 2 weeks or more after your due date, your health care provider may recommend labor induction.

A health care provider may also recommend labor induction if there is a health risk to mother or fetus.

Health care providers use a scoring system, called the Bishop score, to determine how ready the cervix is for labor. The scoring system ranges from 0 to 13. A score of less than 6 means the cervix may need a procedure to prepare it for labor.

Preparing the Cervix for Labor

If the cervix is not ready for labor, a health care provider may suggest one of the following to ripen the cervix:

Stripping the membranes. Your health care provider can disconnect the thin tissue of the amniotic sac containing the fetus from the wall of the uterus. Stripping the membranes causes the body to release prostaglandins (pronounced pros-tuh-GLAN-dins), which soften the cervix and cause contractions.
Giving prostaglandins. This drug may be inserted into the vagina or given by mouth. The body naturally makes these chemicals to ripen the cervix.
Inserting a catheter. A small tube with an inflatable balloon on the end can be placed in the cervix to widen it.

How is labor induced?

Once the cervix is ripe, a health care provider may recommend one of the following techniques to start contractions or make them stronger:

Amniotomy (pronounced am-nee-OT-uh-mee).A health care provider uses a tool to make a small hole in the amniotic sac, causing it to rupture (or the water to break) and contractions to start.
Giving oxytocin (also called Pitocin). Oxytocin is a hormone the body naturally makes that causes contractions. It is given to start labor or to speed up labor that has already begun.

Can induction be requested?

In most cases, induction is limited to situations when there is a problem with the pregnancy, or when a baby is overdue. But sometimes labor induction is requested for reasons other than a problem with the pregnancy.

A woman might want labor induction for several reasons, including:

Physical discomfort at the end of pregnancy
Concern with getting to the hospital in time
Ensuring her own health care provider or midwife can be at the delivery
Ensuring her spouse or partner can be at the delivery
Scheduling issues with work or child care

It is best not to induce labor before 39 weeks of pregnancy (full term) unless there is a medical reason. Preterm infants (born before 37 weeks) and early term infants (born in the 37th and 38th weeks of pregnancy) are at increased risk of illness and even death.

What is vaginal birth after cesarean (VBAC)?

VBAC refers to successful vaginal delivery of a baby after a woman has delivered a baby by C-section in a previous pregnancy.

In the past, pregnant women who had a prior cesarean delivery would automatically have another C-section. But research shows that, for many women who had prior C-sections, attempting to give birth vaginally—called a trial of labor after cesarean delivery (TOLAC)—should be considered.

When is VBAC appropriate?

VBAC may be a safe and appropriate choice for some women, including those:

Whose prior cesarean incision was across the uterus toward its base (called a low-transverse incision), the most common type of incision. Note that the incision on the uterus is different than the incision on the skin.
With two previous low-transverse cesarean incisions
Who are carrying twins
With an unknown type of uterine incision

Benefits of VBAC include:

No abdominal surgery
A lowered risk of hemorrhage and infection, compared with a C-section
Faster recovery
Possibly avoiding the risks of many cesareans, such as hysterectomy, bowel and bladder injury, infection, and abnormal placenta conditions
Greater likelihood of being able to have more children in the future

NICHD research has shown that among appropriate candidates, about 75% of VBAC attempts are successful. A 2010 NIH Consensus Development Conference on Vaginal Birth After Cesarean evaluated current data on VBAC and issued a statement determining that it is a reasonable option for many women.

In addition, NICHD-supported researchers developed a way to calculate a woman's chances of a VBAC. Access the calculator. Please note that this calculator only determines the likelihood of VBAC; it does not guarantee success.

But it is still possible that a woman will have to have a cesarean after having a trial of labor. Most risks associated with TOLAC are similar to those associated with choosing a repeat cesarean. They include:

Uterine rupture
Maternal hemorrhage and infection
Blood clots
Possible need for a hysterectomy

A woman considering VBAC should discuss the issue with her health care provider.

What are some common complications during labor and delivery?

Labor and delivery are different for everyone. Complications sometimes happen. Possible complications include (but are not limited to):

Labor that does not progress. Sometimes the cervix does not dilate in a timely manner to ready the body for delivery. If labor is not progressing, a health care provider may give the woman medications to speed up labor, or the woman may need a cesarean delivery.
Abnormal heart rate of the baby. Many times an abnormal heart rate during labor does not mean there is a problem. A health care provider will likely ask the woman to switch positions to help the infant get more blood flow. In certain instances or if test results show there is a problem, delivery might have to happen right away. When this happens, the woman is more likely to need a cesarean delivery, or the health care provider will need to do an episiotomy (a surgical cut between the vagina and anus) to widen the vaginal opening for delivery.
Perinatal asphyxia. This condition occurs when the baby does not get enough oxygen in the uterus, during labor and delivery, or just after birth.
Shoulder dystocia. In this situation, the infant’s head has come out of the vagina but one of the shoulders becomes stuck.
Excessive bleeding. If delivery results in tears to the uterus or if the uterus does not contract to deliver the placenta, heavy bleeding can result. Worldwide, such bleeding is a leading cause of maternal death.6 The NICHD has supported studies to investigate the use of misoprostol to reduce bleeding, especially in resource-poor settings.

Labor and Delivery: Other FAQs

Basic information for topics, such as "What is it?" is available in the Topic Information section. In addition, Frequently Asked Questions (FAQs) that are specific to a certain topic are answered in this section.

What is false labor, and what are Braxton Hicks contractions?
How are labor and delivery different for a woman having multiple babies?
What is the APGAR test?
Are there added risks for older women during labor and delivery?
What should women consider when choosing to deliver outside a hospital setting?
Is giving birth in water beneficial?
What are preterm labor and birth?

What is false labor, and what are Braxton Hicks contractions?

False labor describes irregular contractions that sometimes happen before true labor begins. These contractions are also called Braxton Hicks contractions. It can be hard to tell the difference between Braxton Hicks contractions and true labor contractions.

The chart below, from the American Congress of Obstetricians and Gynecologists, shows some ways that Braxton Hicks contractions differ from true contractions.

Type of Change	False Labor	True Labor
Timing of contractions	Do not come regularly and do not get closer together	Come at regular times and get closer together over time. Each lasts about 30 to 70 seconds.
Change with movement	Contractions may stop when walking or resting, or they may stop with a change of position.	Contractions continue despite movement.
Strength of contractions	Usually weak and do not get much stronger, or may start strong and get weaker	Get steadily stronger
Pain of contractions	Usually felt only in the front	Usually starts in the back and moves to the front

How are labor and delivery different for a woman having multiple babies?

Women having multiples?twins, triplets, or quadruplets, for example?are more likely to have certain complications during labor and delivery. The most common complications are preterm labor and preterm birth.

Preterm labor is labor that starts before 37 weeks of pregnancy. Preterm labor can result in preterm birth. More than half of all twins are born preterm. Preterm infants can have problems with breathing and eating and may have to stay in the hospital longer than other infants.

Women having multiples are also more likely to need a cesarean delivery.

What is the APGAR test?

An APGAR test, performed 1 minute and 5 minutes after birth, determines whether a newborn infant needs help breathing or is having heart problems. A health care provider assesses the following aspects of an infant's health:

Skin color
Heart rate
Reflexes (response to stimulation such as a mild pinch)
Muscle tone
Breathing

Based on this examination, the health care provider gives the infant an APGAR score of 1 to 10. The higher the score, the better the infant is doing.

Are there added risks for older women during labor and delivery?

Women older than 35 are at higher risk for preterm labor and preterm birth. Preterm infants can have serious short- and long-term health problems.

Older women are also more likely to have a stillbirth, which is when a fetus dies in the uterus after 20 weeks of pregnancy.

Women in their 30s are also more likely than younger women to need a cesarean delivery.

What should women consider when choosing to deliver outside a hospital setting?

Although most women give birth in hospitals, some families choose a home birth or birth in an out-of-hospital birthing center. The American Academy of Pediatrics (AAP) and the American Congress of Obstetricians and Gynecologists (ACOG) state that births in hospitals or birthing centers are the safest options.

If you are thinking about giving birth outside a hospital, you should talk to your health care provider about the risks and benefits.

Women who are good candidates for home birth6:

Are generally in good health
Have not had a previous cesarean delivery
Do not have pregnancy-related health problems or illness
Do not have multiples
Have a fetus with good size and health
Have a fetus in the head-down position
Go into labor at 37 weeks or later

Planned home births should have the following resources in place:

A certified nurse-midwife, certified midwife, or practicing physician
At least one appropriately trained individual whose primary responsibility is the care of the newborn infant
Quick access to health care providers who can provide consultation if complications happen
A reliable plan for safe and fast transportation to a nearby hospital in case of an emergency

Is giving birth in water beneficial?

Being immersed in water during early labor may help with pain. However, there are no proven health benefits to giving birth in water for either mother or baby, according to the AAP and ACOG. Water births have serious risks, including infections and drowning. ACOG recommends that women give birth in water only as part of a well-designed clinical trial.

What are preterm labor and birth?

Labor and birth are considered preterm, also called premature, if they occur before 37 weeks. Preterm labor and birth share many features with regular labor and delivery, but they also have specific features all their own. For this reason, preterm labor and preterm birth are addressed in a separate topic.

Source: NICHD, NIH