Hegar’s sign is a now outdated method for detecting pregnancy. The test is not specific, meaning it cannot reliably detect if someone is not pregnant. Hegar’s sign involves softening of the cervix.
The sign is usually detectable in the second half of the first trimester, between weeks 6 and 12.
Doctors may need to perform a pelvic exam to confirm the presence of Hegar’s sign. Detecting Hegar’s sign was one of several methods doctors used to detect pregnancy before reliable blood and urine tests became available.
Read on to learn more about Hegar’s sign.
Hegar’s sign refers to a physical change that occurs in pregnancy. Doctors often used it in conjunction with other symptoms — such as the absence of a period — to detect pregnancy. However, they do not typically use this method anymore.
Changes in relation to Hegar’s sign specifically affect the cervical isthmus, the part of the cervix that connects the vaginal part of the cervix with the uterus.
Early in pregnancy, various hormones increase blood flow to the uterus and cervix. Hormones responsible for this change include progesterone, estrogen, and human chorionic gonadotropin (HCG). These hormones may also be responsible for other changes in the tissue of the cervix that affect its shape and texture. Additionally, the cervix may appear wider and softer during a doctor’s examination.
This increased blood flow can makes the cervix softer, especially with downward pressure from the uterus. However, it is not a specific sign and means it cannot rule out pregnancy.
Hegar’s sign may be present in nonpregnant people or absent in pregnant people.
A doctor checks for Hegar’s sign using a bimanual pelvic exam. This requires inserting one or more fingers into the vagina to feel for the cervix while externally pressing on the uterus through the abdomen.
A doctor first locates the upper portion of the uterus through the lower abdomen. It should feel firm compared with the lower portion of the uterus and cervix, which should feel soft. With gentle downward pressure on the uterus, the cervix may open slightly.
While a person cannot easily perform a test for Hegar’s sign on themselves, they can look for symptoms suggestive of Hegar’s sign. If they are familiar with the typical feel and texture of their cervix, they may notice that it feels softer than usual or that the opening feels slightly open.
No recent research has assessed how reliable Hegar’s sign is as an indicator of pregnancy. There are tests better at detecting pregnancy available, so doctors do not usually use Hegar’s sign.
If a person suspects they are pregnant, they
Typically, pregnancy tests look for a particular hormone, HCG.
A person may use a home pregnancy test first. These are available over the counter and provide results within a few minutes. With correct use, home pregnancy tests can detect pregnancy accurately.
Home pregnancy tests have also replaced homemade pregnancy tests.
Visiting a doctor before or after a home pregnancy test may be beneficial. A doctor may use more sensitive urine and blood tests to confirm a pregnancy.
In contemporary medicine, now that there are reliable pregnancy tests, there is no need to rely on other early signs of pregnancy.
Still, someone might be interested in how pregnancy changes the body. Two other early signs, besides Hegar’s sign, often occur in pregnant individuals:
This sign becomes noticeable between weeks 4 and 8 of pregnancy. It causes softening of the cervix because of the enlargement of cervical blood vessels. The cervix may also appear larger.
Chadwick sign begins in weeks 6 to 8 and continues for the duration of pregnancy, usually disappearing after birth. It causes a bluish tinge to the vagina, vulva, and cervix because of increased blood flow to veins.
Like Hegar’s sign, neither sign is a reliable indicator of pregnancy. In past times, when diagnosing pregnancy, doctors often looked for other signs along with Hegar’s sign, such as:
- the absence of periods
- changes in the look, shape, or feel of the breasts
- fetal movement
- morning sickness
- changes in the color of the vagina
If anyone has any concerns during pregnancy, they can consult a doctor. A person may wish to seek medical attention if they
- bleeding or leaking from the vagina
- problems with blurred vision
- severe swelling of the face, hands, or fingers
- long lasting or painful headaches
- fever or chills
- vomiting a lot or having persistent nausea
It may not always indicate a serious medical issue, but a healthcare professional can help put someone’s mind at ease.
Pregnancy causes several changes in the body that may present as external signs, including Hegar’s sign. A person may also experience various pregnancy symptoms. However, these signs and symptoms are not conclusive proof of pregnancy. They can occur in people who are not pregnant or not be present in pregnant individuals.
Pregnancy testing and ultrasounds are more reliable indicators of pregnancy. They are also widely accessible, rendering Hegar’s and other early pregnancy signs mostly obsolete.
However, providers may rely on these signs in conjunction with other symptoms, such as the absence of a period, when more reliable tests are unavailable.