Cervix Dilation Chart: Signs, Stages And Procedure To Check

check_icon Research-backed

Image: Shutterstock

IN THIS ARTICLE

Cervix dilation is the opening of the cervix, the neck of the uterus, during childbirth. Body changes during the labor process to allow the baby to pass through the birth canal. Although it is exciting to hold the baby, many women may be nervous and worry about the labor pain and delivery near the due date. Knowing these changes may help them to stay calm.

Childbirth includes three stages, and cervical dilation is crucial since it allows the baby to come out. Vaginal delivery may not be possible if there is no adequate cervical dilation during the labor. Doctors may also use various interventions to dilate the cervix if there is a delay. Read on to learn more about the signs, evaluation, and process of cervix dilation during labor.

What Is Cervix Dilation?

It is the opening of the neck of the uterus, which happens in the first stage of labor. The cervix dilates (uterus opens) due to contractions, and is a vital part of labor and delivery. The dilation is measured in centimeters. It starts from 1cm and grows to 10cm when it is called a complete dilation (1).

If your due date is around the corner and your cervix is dilating, then it could mean you will soon get into labor. Typically, the cervix starts to dilate in the first phase of labor, which is also called the latent phase (1).

Dilation And Effacement: What Is The Difference?

The stretching and thinning of the cervix is called effacement. Cervical effacement is measured in percentage and mostly happens before dilation. The cervix thins and softens at first, and then opens. This happens when labor begins, which is usually around week 37. However, in some women, it could happen during week 38 or later.

Usually, in the first pregnancy, the cervix dilates during labor or after the contractions start. And in some cases, cervical effacement and dilation might happen just before the labor (2). As every pregnancy is different, the occurrence of effacement and dilation can differ.

How Do You Know If Your Cervix Is Dilating?

You will be able to notice even the slightest of changes in the body if you are observant as you near the due date. The following signs indicate that the cervix is dilating.

  1. Lightning crotch: It is the sudden and intense pain experienced in your vagina when your baby descends. Some pregnant women say that the pain feels like a punch in the crotch. When you experience such pain near your due date, it could mean that your baby is positioning for delivery (3).
  1. Uterine contractions: When contractions are frequent and painful, it is most probably a sign of approaching labor, effacement, and dilation (4).
  1. Ruptured membranes or breaking of water: This generally happens during the active phase of stage one labor. When a gush of water is released, the pressure might open the cervix.
  1. Mucus plug discharge: Mucus plug works as a seal to your cervix, and protects your little one from bacteria. So when your cervix opens, the mucus plug comes out (5).
  1. Bloody show: Brown or pink colored discharge could be a result of dilation. If you start noticing some stains, then it might mean your cervix has dilated (6).

How Does Checking Cervix Dilation Help?

Checking cervical dilation helps you to know how close you are to labor and the effective management of labor. When your due date is nearing or has passed, your doctor may check the cervix to see if it is dilated.

Procedure To Check The Cervix For Dilation

Doctors usually check the dilation using their fingers. It is a sterile method and the dilation is measured in centimeters (7) (8).

Steps to check cervix dilation: Follow these steps to check if the cervix is dilated.

i. Use two fingers: Index and middle fingers are inserted into the vagina and against the cervix to gauge the opening. Avoid the anal area.

ii. Assess the dilation: The two fingers should feel the cervix and the opening to assess the length.

You can use the cervix dilation chart to compare your dilation with.

Cervix Dilation Chart

The below chart has been taken from the US Operational Obstetrics and Gynecology (8).

Length in cmAssessment
1.5cmOne finger fits in tightly and touches the head of the fetus
2cmOne finger is loose, and there is no space for the second finger
3cmTwo fingers fit in tightly inside the cervix
4cmTwo fingers are loose in the cervix
6cm2cm of the cervix is palpable on two sides
8cm1cm of the cervix is palpable on two sides
9cmLess than 1cm is left/only anterior lip of cervix felt
10cmCervix is not felt around the head of the fetus

Although professionals generally recommend checking of cervical dilation, there are certain cases where they do not suggest it.

When Not To Check Your Cervix During Pregnancy?

If your doctor finds it risky to check cervical dilation, then do not attempt it. Cervical dilation should only be done when your medical professional has recommended it. Otherwise, do not attempt it.

Next, we see if it is possible to dilate the cervix to speed up the labor process.

Are There Ways To Dilate The Cervix?

Yes, there are natural and medical ways to dilate the cervix. To dilate the cervix, it has to be softened (cervical ripening) first. Usually, medical experts prefer waiting for it to happen naturally. But in some cases, it becomes necessary to dilate the cervix and induce labor.

Some of the natural methods include walking, using a birthing ball, taking herbal supplements, indulging in sexual intercourse, and nipple stimulation. Medical methods include medications and medical/surgical procedures such as stripping of the membranes (9).

Cervix dilation is the opening of the cervix during labor to facilitate childbirth. The cervix dilates gradually from the first phase of labor till delivery. If the cervical dilation is inadequate, doctors may recommend cesarean section delivery. Sudden pain called lightning crotch, water breaks, and intense uterine contractions can be associated with cervical dilation near delivery. You may check the cervical dilation using two fingers if your doctor permits it. The use of birthing balls, walking, sexual intercourse, and nipple stimulation are some of the natural ways to dilate the cervix for delivery.

Key Pointers

  • The cervix dilates or opens due to contractions before labor, unlike effacement, which is the thinning and stretching of the cervix before labor.
  • The indicators of cervix dilation include contractions, breaking of water, and discharge of mucus or blood.
  • Some natural ways to dilate the cervix are walking, sexual intercourse, and the use of a birthing ball.

References:

MomJunction's articles are written after analyzing the research works of expert authors and institutions. Our references consist of resources established by authorities in their respective fields. You can learn more about the authenticity of the information we present in our editorial policy.
1. What Happens During Labor: Stages of Labor; Beth Israel Deaconess Medical Center
2. Cervical Effacement and Dilatation; Michigan Medicine University Of Michigan
3. Braxton-Hicks or Real Labor Contractions; Epigee Women’s Health
4. Recognizing Premature Labor; UCSF Health
5. A. Shepherd and et al.; The purple line as a measure of labour progress: a longitudinal study; BMC Pregnancy & Childbirth (2010)
6. How to tell when labor begins: Frequently asked questions labor, delivery, and postpartum care; The American College of Obstetricians and Gynecologists (2011)
7. Nursing Care of Childbearing Families: Clinical Education Center and Simulation; University of Colorado Denver
8. Operational Obstetrics & Gynecology: Labor and Delivery; The Healthcare of Women in Military Settings
9. J. L. Tenore; Methods for Cervical Ripening and Induction of Labor; American Academy of Family Physician (2003)
Was this information helpful?
thumbsupthumbsdown
The following two tabs change content below.

Dr Bisny T. Joseph

Dr. Bisny T. Joseph is a Georgian Board-certified physician. She has completed her professional graduate degree as a medical doctor from Tbilisi State Medical University, Georgia. She has 3+ years of experience in various sectors of medical affairs as a physician, medical reviewer, medical writer, health coach, and Q&A expert. Her interest in digital medical education and patient education made... more

Dr. Sangeeta Agrawal

(FRCOG, MD, DNB, DGO)
Dr. Sangeeta Agrawal worked in Royal London, St. Bartholomew’s, North Middlesex and Barnet General hospitals in London. Currently, she runs her own clinic in Mumbai. She is also attached to Bhatia Hospital, Breach Candy Hospital, Wockhardt Hospital, and Global Hospital. Her areas of expertise include obstetrics and gynecology, involving teenage care, antenatal, intrapartum, post-natal care, painless labor, fertility control, menopause... more

LATEST ARTICLES