The purpose of screening is early diagnosis and treatment. Screening tests are usually administered to people without current symptoms, but who may be at high risk for certain diseases or conditions.

All pregnant women are screened for factors that may increase their risk of preterm labor. For women at low risk of preterm labor, there are no recommendations for further screening.

The benefit of screening high risk women for preterm labor is controversial. Some methods of screening for preterm labor that may be used to screen high risk women include:

Risk Factor Assessment

At the first prenatal visit and later in pregnancy, a structured list of ]]>risk factors]]> can be checked and a risk score determined for preterm delivery.

In order for risk identification to be helpful, it must be combined with a program for modifying those risk factors which can be modified. These programs are usually community based; examples include the Alabama Preterm Birth Prevention Project, the Better Birth Outcomes trials, and other community-based initiatives.

Fetal Fibronectin

During the pelvic exam, your doctor may swab your cervix to test for fetal fibronectin (fFN). fFN acts as a glue to attach the amniotic sac to the lining of the uterus. It is normal for fFN to be in cervical secretions for the first 22 weeks of pregnancy. However, if fFN is present in the outer cervix beyond weeks 22-34, this glue may be breaking down earlier than it should. fFN may be a sign of preterm labor.

The presence of fFN (positive test result) is not a good predictor of whether you are at risk of preterm birth. If fFN is not present, your pregnancy is likely to continue at least another two weeks. The absence of fFN (negative test result) is a good predictor that you are not at risk of a preterm birth at this time.

Cervical Length

Your doctor may measure your cervix at the first prenatal visit. During pregnancy, your cervix is monitored for changes. If your cervix is getting shorter, that means it's beginning to efface (thin out), placing you at a higher risk for preterm delivery.

Home Uterine Activity Monitoring

A uterine activity monitor can measure and time your contractions. The monitor is strapped around your belly and is worn at home. It can be worn for up to ten weeks. Information from the monitor is sent to a central monitoring office where a nurse looks for signs of preterm labor.

Home uterine activity monitoring is not recommended in women with or without risk factors for preterm labor. A 2002 study by the National Institute of Child Health and Human Development (NICHD) found that uterine monitors did not predict preterm labor. The US Preventive Services Task Force stated that there is not enough evidence to either recommend or advise against home uterine activity monitoring as a screening test for preterm labor in high-risk pregnancies. The American College of Obstetricians and Gynecologists (ACOG) does not recommend the use of this device.