Which statement about fetal fibronectin (fFN) is most accurate?

Fetal fibronectin (fFN) serves as a valuable biomarker for the identification of preterm labor, particularly in symptomatic women. This glycoprotein is found in the extracellular matrix and is typically present at the maternal-fetal interface during pregnancy. When detected in cervical or vaginal secretions, particularly between 22 and 34 weeks of gestation, it may suggest that preterm labor is a possibility. The presence of fFN can indicate that the membranes may be in a weakened state, increasing the risk for premature birth.

It's important to note that while a positive fFN test can suggest the likelihood of preterm labor, a negative test is more informative in ruling it out, thereby providing reassurance. However, testing for fFN cannot determine fetal sex, nor does it signal the onset of labor in all pregnant women. Therefore, its primary and most accurate role in clinical practice is as a marker for identification of preterm labor, supporting decision-making related to management and potential interventions for at-risk pregnancies.