Labor is a 3-stage process leading up to birth. The first stage begins when a pregnant woman's uterus contracts and her cervix dilates. The uterine contractions that occur with labor are caused by the hormones oxytocin and prostaglandin. During the second stage of labor, the baby is pushed through the vagina. The third stage of labor is the delivery of the placenta and fetal membranes, which happens just a few minutes after the baby is born. The length and experience of labor varies considerably among women.
Your doctor uses certain guidelines to determine if your labor is progressing normally. Occasionally, labor does not progress normally, and medical assistance or a cesarean section may be needed. If labor begins before the 37th week of pregnancy, it is considered preterm. If you have any symptoms of labor before the 37th week, you should call your doctor immediately.
There are many different aspects to labor. Here is some information on signs, stages, and what you can expect.
Knowing the Signs of Labor
Your due date is only an estimate of when labor will begin. It is normal for labor to begin anytime within 2 weeks before or after your due date. Labor will begin with regular contractions of the uterus and the opening and thinning of the cervix. When your body is preparing for labor, you may experience the following signs:
It will feel as if your baby has dropped lower in your abdomen. This happens when your baby's head settles deeper into your pelvis. This occurs a few weeks to a few hours before labor begins.
Mucus Plug or "Show"
You may pass a thick plug of cervical mucus or have an increase of vaginal discharge that may look clear, slightly bloody, or pink. The mucus plug is pushed into the vagina when the cervix begins to open. This may occur several days before labor begins or during the onset of labor.
You may feel a continuous trickle or a gush of fluid from your vagina. This is caused when the amniotic sac breaks, releasing the fluid that surrounded your baby during pregnancy. The water may break before labor starts, or it may not break until after labor has begun. Even if you do not have contractions, call your doctor if this happens.
When regular contractions occur, you may actually be going into labor. Effective labor contractions (as opposed to false labor contractions) are usually felt in the abdomen, but with a heavy sense of low-back pressure or discomfort.
When you actually go into labor, you will experience the following signs:
- Contractions that come at regular intervals and last about 30-40 seconds. The contractions will become closer together with increasing intensity.
- Contractions that do not go away when you move around.
- Pain from the contractions that may be felt in the back and the front of your abdomen.
False labor pains, also known as Braxton-Hicks contractions, often occur in the third trimester. They may be uncomfortable or painful and can lead you to think that you are going into actual labor. It can be difficult to tell the difference between false and true labor. In fact, sometimes the difference can only be determined by a vaginal and cervical exam. False labor may be characterized by:
- Irregular cramps that do not get consistently closer.
- Contractions that stop when you walk, rest, or change position.
- Contractions that are felt only in the abdomen (not in the lower back).
The Stages of Labor
First Stage of Labor
During the first stage of labor, regular contractions begin causing the cervix to dilate. At the end of the first stage, your cervix will be completely dilated. The first stage of labor consists of a latent phase and an active phase. In the latent phase, your cervix slowly dilates up to 3-4 centimeters (cm)—a process that can take 8 or more hours. It is marked by fairly mild contractions that last about 30-40 seconds and shorten to about 5 minutes apart.
The active first stage of labor starts when your cervix is about 3 cm dilated and lasts until you are fully dilated (10 cm). Contractions become more intense and closer together. The contractions become increasingly more painful. Some women request painkilling drugs and some women get an epidural to decrease pain. During this phase, you may want to change positions frequently, sit up, begin controlled breathing, or even get up and walk around. A warm bath or shower may help you relax. You will also benefit from coaching and support, which will help to increase relaxation.
At the end of the active first stage, contractions become very intense, about 2-3 minutes apart, and last from 60 to 90 seconds each. You will need to concentrate on your breathing and will benefit from a lot of coaching. During this phase, you may experience the following signs:
- Hot and cold flashes
- Sensitivity to the environment
- Nausea or vomiting
- Leg cramps
- The urge to push
Second Stage of Labor
The second stage of labor starts when your cervix is fully dilated. Contractions will be very strong and painful, will last about 60 seconds, and will come at intervals of about 2-3 minutes. You will have an intense urge to push. This stage can last anywhere from a few minutes to up to 18 hours (average 8) for a first-time mother and shorter if have delivered before. You may feel a stretching or burning sensation as the baby's head is pushed out of your vagina. At the end of the second stage of labor, after your baby is born, you will feel greatly relieved and excited.
Third Stage of Labor
The third stage of labor directly follows delivery of your baby and ends with the delivery of the placenta, usually within 30 minutes of the birth. During this stage, your uterus will contract and expel the placenta and membranes that have surrounded the fetus in your uterus. You will feel mild contractions that are very different from labor contractions. During these contractions, you may be encouraged to push. You also may be given intravenous oxytocin to assist uterine contractions.
After the placenta is delivered, you may need some sutures placed to close any tears that occurred during delivery. You will also be closely monitored for complications, such as bleeding and infection.
Your labor will be carefully monitored by your doctor. Throughout labor, your vital signs, uterine contractions, and your baby's heart rate and well-being will be checked. These can be checked manually or with an electronic monitor. If any problems are detected, your doctor can take the necessary action.
Labor can be a long and painful process. Knowing what to expect can help prepare you to meet the newest member of your family.
Family Doctor—American Academy of Family Physicians
The American Congress of Obstetricians and Gynecologists
The Society of Obstetricians and Gynaecologists of Canada
Women's Health Matters
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Labor and birth. Office on Women's Health website. Available at: https://www.womenshealth.gov/pregnancy/childbirth-beyond/labor-birth.html. Updated September 27, 2010. Accessed October 24, 2016.
Management of routine labor. EBSCO DynaMed Plus website. Available at:http://www.dynamed.com/topics/dmp~AN~T905272/Management-of-routine-labor. Updated April 11, 2016. Accessed October 24, 2016.
Preterm labor. EBSCO DynaMed Plus website. Available at:http://www.dynamed.com/topics/dmp~AN~T115273/Preterm-labor. Updated August 19, 2016. Accessed October 24, 2016.
Stages of childbirth: Stage I. American Pregnancy Association website. Available at: http://americanpregnancy.org/labor-and-birth/first-stage-of-labor. Updated August 2015. Accessed October 24, 2016.
Last reviewed October 2016 by Michael Woods, MD