What Is Chadwick's Sign?

Chadwick's sign is one of several physical changes that occur during pregnancy. It is an early sign that a person is probably pregnant. It appears as a dark bluish or purplish discoloration of the vaginal tissue, vulva, or cervix, which is caused by an increase in venous (from the veins) blood flow to the area.

Other early signs of pregnancy include Goodell’s sign (a softening of the cervix at around six to eight weeks of gestation) and Hegar’s sign (softening of the lower segment of the uterus, which occurs around six to 12 weeks of gestation).

These changes are considered probable signs of pregnancy, but they do not definitively indicate a person is pregnant.

Chadwick's Sign and Pregnancy Diagnosis

Chadwick's sign is not a definitive indicator that a person is pregnant. Tests will need to be done to confirm a pregnancy, often starting with an at-home pregnancy test.

A healthcare provider can then use several methods to confirm a pregnancy. Common ways to diagnose pregnancy include:

• A thorough history (such as gathering information about a person’s menstrual periods)
• A physical examination (to check for any presumptive signs of pregnancy, including Chadwick’s sign)
• Laboratory tests (such as a test that detects levels of human chorionic gonadotropin [hCG], a hormone produced by the placenta during pregnancy)
• Sonography (which uses ultrasound waves to bounce off structures and create images of the uterus)

Conditions That Mimic Chadwick’s Sign

If a pregnancy is not confirmed, other causes will need to be evaluated. Some medical conditions can mimic the symptoms of pregnancy, including Chadwick’s sign.

There are other conditions that can cause bluish discoloration of the cervix:

• Cervical endometriosis: This condition can cause blue cervical lesions and other symptoms, such as red, black, or blue cervical lesions; discharge; dysmenorrhea (painful menstruation); and pelvic pain.
• Adenomyosis: When endometrial tissue is present in the uterine muscle, it may also affect the cervix if a mass protrudes into the endocervical canal.
• Peudocyesis (false pregnancy): False pregnancy occurs when a person believes they are pregnant when they are not. The belief can trigger the brain to release pregnancy hormones such as estrogen and progesterone. An increase in hormone levels causes a person to have the physical signs and symptoms of pregnancy, including Chadwick's sign.

Pregnancy Symptoms Categories

There are several categories to describe signs of pregnancy, including presumptive, probable, and positive signs.

Presumptive (Possible) Signs of Pregnancy

Presumptive signs are those that raise some suspicion that a person might be pregnant. These signs are subjective, meaning they are reported by the patient.

• Nausea and vomiting (morning sickness)
• Missed menstrual periods (amenorrhea)
• Severe fatigue
• Breast enlargement
• Painful breasts
• An increase in urination
• Quickening (a feeling of movement in the lower abdomen, usually felt for the first time at around 16 to 22 weeks of gestation.

Probable Signs of Pregnancy

Probable signs of pregnancy are those that are strongly linked with pregnancy but can also be symptoms of other underlying conditions. Probable signs of pregnancy include:

• Chadwick’s sign
• Goodell’s sign
• Hegar’s sign
• Jacquemier's sign

Other Signs

There are also other signs that indicate pregnancy is likely but not certain. These signs may seem like positive signs of pregnancy but can also be brought on by other causes.

These signs include:

• A positive hCG test
• External ballottement (palpation performed by a doctor that causes the fetus to bounce back against their fingers when the uterus is pushed)
• Braxton Hicks contractions (labor pains that are considered false labor because they do not cause cervical changes, such as dilatation)
• An enlarged uterus

Positive Signs of Pregnancy

Positive signs of pregnancy are those that have no other underlying cause. Signs that are considered definitive of pregnancy include:

• Doppler (an electronic device that detects fetal heart sounds)
• Fetal movements (felt or seen by the diagnostician)
• Ultrasound (sonography; detects the fetus)
• Birth of the baby

When to Call a Doctor

Chadwick's sign is not usually the first indicator of pregnancy, but it can appear early on and might prompt you to confirm that you are pregnant.

If you notice the discoloration in your vaginal area or have any signs you think could be those of pregnancy, make an appointment with your doctor to have the diagnosis confirmed.

Summary

Chadwick's sign is a bluish-purple discoloration of the cervix that can occur in early pregnancy. While it can be a sign of pregnancy, it does not definitively mean that someone is pregnant. There are also other conditions that can cause the change, such as cervical endometriosis.

A Word From Verywell

If you experience cervical discoloration, your doctor can use other diagnostic methods to confirm that you are pregnant or find out what underlying condition is causing the changes if you are not pregnant.

Chadwick's sign is an expected physical change related to pregnancy. However, if you feel self-conscious about it (especially during sexual activity), talk about it with your partner. Explaining why it occurs will help you both feel more comfortable and encourage an open conversation about all the changes your body will go through during pregnancy.

Frequently Asked Questions

Why does Chadwick's sign occur?

Chadwick's sign—the bluish discoloration of the vagina, vulva, and cervix—occurs when there is an increase in blood flow to the area triggered by an increase in hormone levels (such as estrogen).

The sign occurs because there is blood congestion in the veins. This happens because there is an increase in base estrogen levels during pregnancy.

How long does Chadwick's sign last?

Chadwick's sign usually shows up about six weeks after conception. It typically subsides during the pregnancy or soon after delivery.