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Reviewed/Revised Sep 2022
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What is labor?

Labor is the first stage of childbirth. During labor the muscles of your womb (uterus) squeeze again and again to push your baby out. These squeezes are called contractions. Contractions stop and start on their own. You don't have any control over them. They get stronger as labor goes along.

It's time to go to the hospital (or birthing center) when one of the following happens:

  • Your water breaks

  • Your contractions last 30 seconds or more and are less than 6 minutes apart

What happens during labor?

Your cervix is the lower part of your uterus where it connects to your vagina. The cervix has a small opening that stays tightly closed while you're pregnant. During labor, your contractions gradually pull the cervix open until it's wide enough for your baby to come out.

Labor has 2 parts:

  • Early labor

  • Active labor

During early labor:

  • Your cervix begins to thin and opens up about 1 to 2 inches (2 to 5 centimeters)

  • Contractions come and go and get stronger and more evenly spaced

  • The pain isn't too bad

During active labor:

  • Your cervix opens fully, about 4 inches (10 centimeters) and thins out completely

  • Your baby drops (moves lower into your pelvis and gets ready to enter the birth canal)

  • You start to feel like you need to push the baby out

  • Pain is more intense

Your water breaking is when the amniotic sac breaks and amniotic fluid comes out of your vagina. This may happen before labor starts or during labor.

How will I know when labor starts?

The main signs of labor are:

  • Contractions, which may feel like menstrual cramps that come and go at regular intervals

  • Back pain

Before contractions or back pain, early signs that labor is about to start include:

  • Bloody show (a small amount of blood and mucus that comes out of your vagina at the start of labor)

  • Your "water breaking"

If your water breaks, you should call your doctor or midwife right away. Usually, labor starts within 24 hours. However, if it doesn’t start within several hours, your doctor or midwife may start your labor with medicines.

If your water breaks more than 6 weeks before your due date, your doctor may give you medicine to stop labor. This lets the baby grow a little more before being born.

When should I go to my hospital or birthing center?

You should go to your hospital or birthing center when one of the following happens:

  • Your water breaks

  • Your contractions last 30 seconds or more and are less than 6 minutes apart

A doctor or midwife will check to see whether you're actually in labor. Near their due date, some women have cramps that feel like labor but aren't. If you’re not in labor yet, you'll be sent home.

If you're in labor, your doctor will:

  • Check your vagina to see if your water has broken and, if it has, check the color of the fluid

  • Touch your cervix to see how far it's open

  • Feel your belly to see what position the baby is in

  • Put an IV into an arm vein to help give you medicines and fluids during labor

If you've delivered a baby before and it was fast (took less than 6 hours), you should let your doctor know as soon as you think labor has started. You'll likely deliver quickly because each labor is usually shorter than the one before.

How do doctors check the baby during labor?

During labor, the main thing that tells doctors how the baby's doing is:

  • The baby's heart rate

Doctors may check the baby’s heartbeat using:

  • A stethoscope

  • An ultrasound device placed on your belly

  • An electronic fetal heart monitor placed inside your vagina to continuously record your baby’s heartbeat

The Vaginal Exam in Labor

How do doctors treat labor pain?

The amount of pain during labor varies. Some women need more pain relief than others during labor. Taking childbirth classes during pregnancy and having a support person with you can help you feel more comfortable during labor and may lower your need for pain medicine.

During pregnancy, you'll talk with your doctor or midwife about what kind of pain relief you want. Pain medicines during labor include:

  • IV opioid pain medicines, such as morphine or fentanyl, which make you more comfortable but may cause your baby to breathe too slowly if you get the medicine too close to when the baby is delivered

  • An epidural block, which is an injection of numbing medicine (local anesthetic) or pain medicine into your lower back to numb nerves around your spinal cord

  • A nerve block, in which doctors inject numbing medicine inside your vagina to block pain signals from major nerves

  • Local anesthesia, shots of numbing medicine around the outside of your vagina just before the baby comes out

Natural childbirth uses relaxation and breathing techniques instead of medicine to control labor pains and lower your need for pain medicine. Some women doing natural childbirth don't use any pain medicine. To prepare, you and a support person usually take childbirth classes over several weeks to learn about labor and how to breathe and relax through it.

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