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When will I go into labor?

What causes labor to start?

What happens to the body when labor begins?

What changes should I watch for?

What is lightening?

What is loss of the mucus plug?

What is the rupture of membranes?

What do contractions feel like?

What are Braxton Hicks contractions?

How will I be able to tell the difference between “false” labor and “true” labor?

How will I know whether to call my provider or go to the hospital?

How long does labor last?

What should I discuss with my health care team before my due date?

How should I plan my trip to the hospital?

What other things should I be doing before labor begins?

Glossary

When will I go into labor?

The average length of pregnancy is 280 days, or 40 weeks. But there is no way to know exactly when you will go into labor. Most women give birth between 38 and 41 weeks of pregnancy. The more you know about what to expect during labor, the better prepared you will be once it begins.

 

What causes labor to start?

No one knows exactly what causes labor to start, although changes in hormones may play a role. Most women can tell when they are in labor, but sometimes it’s hard to tell when labor begins.

 

What happens to the body when labor begins?

As labor begins, the cervix opens (dilates). The muscles of the uterus contract at regular intervals. When the uterus contracts, the abdomen becomes hard. Between the contractions, the uterus relaxes and becomes soft.

 

What changes should I watch for?

Certain changes may signal that labor is beginning. These changes include:

  • lightening
  • loss of the mucus plug
  • rupture of membranes
  • contractions

You might or might not notice some of these changes before labor begins.

 

What is lightening?

This is the sensation that the fetus has dropped lower and the head settles deep in your pelvis. Because the fetus isn’t pressing on your diaphragm, you may feel “lighter.” Lightening can happen anywhere from a few weeks to a few hours before labor begins.

 

What is loss of the mucus plug?

A thick mucus plug forms at the cervix during pregnancy. When the cervix begins to dilate several days before labor begins or at the start of labor, the plug is pushed into the vagina. You may notice an increase in vaginal discharge that is clear, pink, or slightly bloody. Some women expel the entire mucus plug.

 

What is the rupture of membranes?

When the fluid-filled amniotic sac that surrounds the fetus during pregnancy breaks, it is called the rupture of membranes. This is also referred to as your “water breaking.” You may feel this as fluid that trickles or gushes from your vagina. If your water breaks, call the office of your obstetrician–gynecologist (ob-gyn) or other obstetric care provider and follow their instructions.

 

What do contractions feel like?

As your uterus contracts, you may feel pain in your back or pelvis. This pain may be similar to menstrual cramps. Labor contractions happen in a regular pattern and get closer together over time.

 

What are Braxton Hicks contractions?

Braxton Hicks contractions can happen for many weeks before real labor begins. These “practice” contractions can be very painful and can make you think you are in labor when you are not. You might notice them more at the end of the day.

 

How will I be able to tell the difference between “false” labor and “true” labor?

Usually, “false” contractions are less regular and not as strong as “true” labor. Time your contractions and note whether they continue when you are resting and drinking water. If rest and hydration make the contractions go away, they are not true labor contractions.

Below is a summary of some differences between true labor and false labor. But sometimes the only way to tell the difference is by having a vaginal exam to find changes in your cervix that signal the start of labor.

Timing and frequency of contractions:
  • True labor contractions come at regular intervals. They have a pattern. As time goes on, they get closer together. Each lasts about 60 or 90 seconds.
  • False contractions do not have a pattern and they do not get closer together. These are called Braxton Hicks contractions.
Change with movement:
  • True labor contractions continue even when you rest or move around.
  • False contractions may stop when you walk or rest. They also may stop with a change of position.
Strength of contractions:
  • True labor contractions steadily get stronger.
  • False contractions are weak and do not get much stronger. They may start strong and then weaken.
Location of pain:
  • Pain from true labor contractions usually starts in the back and moves to the front.
  • Pain from false contractions usually is felt only in the front.

 

How will I know whether to call my provider or go to the hospital?

If you think you are in labor (or are not sure), call your ob-gyn or other obstetric care provider. You should go to the hospital if you have any of these signs:

  • Your water has broken and you are not having contractions.
  • You are bleeding heavily from the vagina.
  • You have constant, severe pain with no relief between contractions.
  • You notice the fetus is moving less often.

 

How long does labor last?

For a woman having her first baby, labor typically lasts 12 to 18 hours. For women who have given birth before, it typically lasts 8 to 10 hours. But every woman is different. Your labor may not be like your mother’s, your sister’s, or your friend’s labor. It may even be different with each child you have. Even so, labor and delivery usually follow a pattern.

 

What should I discuss with my health care team before my due date?

Well before your due date, talk about the following with your health care team:

  • The right time to call your ob-gyn or other obstetric care provider
  • How to reach your doctor, provider, or nurse after office hours
  • Whether to call first or go directly to the hospital
  • Special steps you should take if you think labor has begun

 

How should I plan my trip to the hospital?

Before labor begins, you can do the following:

  • Determine how far you live from the hospital and how long it will take to get there.
  • Rehearse going to the hospital to get a good sense of how long it might take to get there.
  • Consider traffic, rush hour, and possible delays on the regular route.

 

What other things should I be doing before labor begins?

  • Pack for the hospital and leave your bag in a handy place, such as a hall closet or the trunk of your car.
  • Plan for who will care for your other children, your pets, and your home when you are in the hospital.
  • Make sure you have a car seat to bring home your baby, and make sure it is installed properly.
  • Talk with your supervisor about who will manage your workload while you are out.

 

Glossary

Amniotic Sac: Fluid-filled sac in a woman’s uterus. The fetus develops in this sac.

Braxton Hicks Contractions: False labor pains.

Cervix: The lower, narrow end of the uterus at the top of the vagina.

Hormones: Substances made in the body that control the function of cells or organs.

Obstetric Care Provider: A health care professional who cares for a woman during pregnancy, labor, and delivery. These professionals include obstetrician– gynecologists (ob-gyns), certified nurse–midwives (CNMs), maternal–fetal medicine specialists (MFMs), and family practice doctors with experience in maternal care.

Obstetrician–Gynecologist (Ob-Gyn): A doctor with special training and education in women’s health.

Uterus: A muscular organ in the female pelvis. During pregnancy, this organ holds and nourishes the fetus.

Vagina: A tube-like structure surrounded by muscles. The vagina leads from the uterus to the outside of the body.


If you have further questions, contact your obstetrician–gynecologist.

FAQ004. Copyright May 2020 by the American College of Obstetricians and Gynecologists


This information is designed as an educational aid to patients and sets forth current information and opinions related to women’s health. It is not intended as a statement of the standard of care, nor does it comprise all proper treatments or methods of care. It is not a substitute for a treating clinician’s independent professional judgment. Read ACOG’s complete disclaimer.