4 years ago
Fetal fibronectin (fFN) is a protein produced during pregnancy and functions as a biological glue, attaching the fetal sac to the uterine lining. During the first trimester and for about half of the second trimester (up to 22 weeks of gestation), fFN is normally present in the cervico-vaginal secretions of pregnant women. In most pregnancies, after 22 weeks, this protein is no longer detected until the end of the last trimester (one to three weeks before labor).
The presence of fFN during weeks 24-34 of a high-risk pregnancy, along with symptoms of labor, suggests that the "glue" may be disintegrating ahead of schedule and alerts doctors to a possibility of preterm delivery.