How Is Premature Labor Diagnosed?

Since it is difficult to predict or prevent premature labor, health care providers often have to cope with managing the condition as it arises.

Contractions alone aren't enough to accurately diagnose premature labor. Diagnosis depends on detecting changes in the cervix by vaginal examination.

Final diagnosis depends on answering two questions:

• Is it really labor?

• Is it really premature?

Is It Really Labor?

When a woman feels that her uterus is contracting and she suspects that she is in preterm labor, she should not hesitate to contact her health care provider.

If labor has in fact begun and the doctor decides to attempt to halt the process, it is most easily accomplished before the situation has progressed too far. Therefore, a woman who suspects she is in labor should not ignore the symptoms.

Only your health care provider can accurately diagnose preterm labor. There are several ways to assess your condition:

• A vaginal exam to determine whether the cervix has begun to shorten (efface) and open (dilate) will be necessary to determine whether the contractions are causing labor.

• Measuring cervical length by transvaginal ultrasound early in pregnancy is a good indicator of the possibility of preterm delivery.

• A swab of cervicovaginal secretions can be tested for the presence of fetal fibronectin (a protein found in fetal membranes and amniotic fluid), which is associated with preterm delivery. A new rapid test has recently become available. If this test is negative, there is a very low risk of delivery in the next two weeks.

• The fact that babies cease having chest movements (fetal breathing) during labor has been employed to try to improve diagnosis. While not infallible, it is true, in general, that if fetal breathing can be seen on ultrasound scan, the woman is unlikely to progress to delivery; whereas if fetal breathing is absent, it is more likely that she is experiencing preterm labor.

Is it Really Premature?

Once your medical care provider has established that you are in labor, he or she must determine if the baby is actually premature before deciding to halt the process. If the date of your conception is well-established by accurate menstrual dates and/or early ultrasound examinations, this is an easy task.

However, if you are seeking medical care for the first time while having contractions, and the actual date of the last menstrual period is not known, you could actually be in normal full term labor with a very small baby. Tests of amniotic fluid contents obtained by amniocentesis will predict the maturity of the fetus.