Dilation, Labor Contractions, and When to Go to the Hospital

Doctor examining pregnant woman
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One of the main concerns expecting parents have in the third trimester is knowing when it’s time to go to the hospital or call the midwife. While it's not uncommon to think that the first contractions are your cue, that's usually not the case. Early labor can last for days, and may not even be true labor. Dilation is an essential part of labor, and it's hard to know how dilated you are unless you are examined by your doctor or midwife.

Understand the stages of labor and the measures by which healthcare providers mark them. This can greatly reduce your stress and help you avoid multiple trips to the hospital before the time is right.

Stages of Labor

No two births are alike, and there's often no way to know how long your delivery will take or what it may entail. Still, childbirth will invariably progress in three clearly defined stages.

Stage One

The first stage begins with the onset of true labor and continues until the cervix is fully dilated to 10 centimeters, and is further divided into three additional stages or phases:

  • Early (or latent) labor: From the onset of labor to 3 cm dilation; may last up to 20 hours in a first birth, and 10 to 12 hours in subsequent births
  • Active labor: Continuation of dilation to 7 cm; lasts an average of 5 hours in first births, and 2 hours in subsequent births
  • Transition: Continuation to dilation of 10 cm; lasts 15 to 60 minutes

It's usually during the second of these three phases—active labor—that it's time to make the move to the hospital or birth center. In advance, your doctor or midwife should give you guidelines to follow.

Stage Two

Once the cervix is fully dilated (10 cm), you'll have to actively push, similar to the sensation of pushing through a bowel movement, until the baby's head is visible from the vaginal opening ("crowning"). If this is your first pregnancy, this stage can take anywhere from 30 minutes to two hours. It includes the birth of your baby.

Stage Three

The third stage is the delivery of the placenta. This usually takes just a few minutes, but can sometimes take up to 30 minutes.

When It's Time to Go to the Hospital

Early labor is the least painful but longest of the three stages, lasting up to 20 hours for first-time deliveries. Contractions will occur every five to 30 minutes and typically last 30 to 45 seconds. In most cases, doctors will advise you to stay home until the contractions are closer together and longer-lasting.

Active labor begins when the contractions come every three to four minutes over an hour-long period and last for roughly 60 seconds. The stage will typically last for three to five hours. If this is your first delivery, you would go to the hospital now. If you've had a child before, you may be asked to come earlier, when the contractions occur every five to seven minutes.

You should go to the hospital if your water breaks—no matter the stage—so your doctor can check the health of the pregnancy and proceed with assisted labor, if necessary. Bloody show, a thick mucus with some blood expelled from the vagina, may also be a sign that you're about to go into labor (but going to the hospital is not necessary at this point).

Arriving at the Hospital

Dilation of the cervix alone does not determine when you are in a labor. In some cases, a woman may only be dilated 1 cm but experience strong and frequent contractions. Others may experience dilation even before labor begins.

That's why, once you arrive at the hospital, you have a pelvic exam to determine how dilated your cervix is. In addition, the doctor, nurse, or midwife looks for the characteristic shortening and thinning of the cervix known as effacement.

Along with dilation, effacement is the process that allows the baby to move into the birth canal. Effacement is measured in percentages, with 0% meaning no thinning of the cervix, 50% meaning half the normal thickness, and 100% meaning fully thinned.

Your healthcare provider uses this and other information to recommend whether you stay at the hospital or return home. Other considerations may include:

  • The position of the cervix (generally tilted forward prior to labor)
  • The position and rotation of the baby
  • Your medical health and history

In the end, there are no hard and fast rules. For example, if you're less than 3 centimeters when you arrive, are not in a lot of pain, and are not planning to use an epidural, going home may be the most reasonable and comfortable option. However, if your water has broken, you're in a lot of pain, or have special medical needs, staying may be the better choice, even if you're less dilated.

Generally speaking, once you are dilated past 5 or 6 centimeters and having regular contractions, most practitioners want you to you remain in the hospital or birth center until your baby is born.

True or False Labor

Sometimes a contraction may not be the sign of true labor. If a contraction is erratic in frequency and strength, it may be something called a Braxton Hicks contraction, also known as false labor. Here's how to spot the differences between the two:

  • Braxton Hicks contractions: These are irregular, do not increase in strength or frequency, and often stop when you walk, rest, or switch positions. Braxton Hicks contractions are constrained to the lower abdominal or pelvic region. They can develop as early as the second trimester but are more common during the third.
  • True labor contractions: These are regular, increase in strength and frequency, do not change if you move or shift position, and originate in the lower back before moving to the front of the abdomen.

While it's easy to mistake a Braxton Hicks contraction for a real one, always watch the pattern to decide whether you're experiencing true labor. Knowing the difference can save you an unneeded trip to the hospital.

7 Sources
Verywell Family uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. American College of Obstetricians and Gynecologists. How to tell when labor begins.

  2. Hanley GE, Munro S, Greyson D, et al. Diagnosing onset of labor: A systematic review of definitions in the research literature. BMC Pregnancy Childbirth. 2016;16:71. doi:10.1186/s12884-016-0857-4

  3. National Institutes of Health. What are the stages of labor?

  4. Penn Medicine. The three stages of labor.

  5. Stanford Children's Health. Overview of labor.

  6. Langen ES, Weiner SJ, Bloom SL, Rouse DJ, Varner MW, Reddy UM, Ramin SM, Caritis SN, Peaceman AM, Sorokin Y, Sciscione A, Carpenter MW, Mercer BM, Thorp JM Jr, Malone FD, Iams JD; Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Maternal-Fetal Medicine Units (MFMU) Network. Association of cervical effacement with the rate of cervical change in labor among nulliparous women. Obstet Gynecol. 2016;127(3):489-495. doi:10.1097/AOG.0000000000001299

  7. American College of Obstetricians and Gynecologists. Is it normal to feel fake contractions?.

By Robin Elise Weiss, PhD, MPH
Robin Elise Weiss, PhD, MPH is a professor, author, childbirth and postpartum educator, certified doula, and lactation counselor.