Fetal fibronectin (fFN) is a fibronectin protein produced by fetal cells and certain types of tumor cells. Fetal fibronectin “leaks” into the vagina if a preterm delivery is likely to occur and can be measured in a screening test. When the fFN test is positive, it is an inconclusive result. A positive result can indicate that a woman will go into preterm labor soon, but she may not go into labor for weeks. When the fFN test is negative, the result is a better predictor. A negative result means that there is little possibility of preterm labour within the next 7 to 10 days, and the test can be repeated weekly for women who remain at high risk. A negative fetal fibronectin test gives a more than 95% likelihood of remaining undelivered for the next 2 weeks.
fFN is also secreted into the urine of patients with bladder cancer (transitional cell carcinoma), and can be detected in the tissue culture supernatants of liver cancer, breast cancer and lung cancer cell lines. The possible onco-fetal relation of fFN gene regulation suggests that fFN could be an early biomarker for certain cancers.
Click the manual Human Fetal Fibronectin XpressCard for more information.