Definition
By Mayo Clinic staffFetal fibronectin is a protein that acts as a "glue" during pregnancy, attaching the amniotic sac — the fluid-filled membrane that cushions your baby in the uterus — to the lining of the uterus.
Fetal fibronectin is often present in vaginal discharge before week 22 of pregnancy. Fetal fibronectin also begins to break down and can be detected in vaginal discharge toward the end of pregnancy.
If your health care provider is concerned about preterm labor, he or she might test a swab of secretions near your cervix for the presence of fetal fibronectin between week 22 and week 34 of pregnancy. A positive fetal fibronectin test is a clue that the "glue" has been disturbed and you're at increased risk of preterm labor.
- Lockwood CJ. Fetal fibronectin for prediction of preterm labor and delivery. http://www.uptodate.com/home. Accessed Jan. 31, 2013.
- Lockwood CJ. Overview of preterm labor and birth. http://www.uptodate.com/index. Accessed Jan. 31, 2013.
- Frequently asked questions. Pregnancy FAQ173. Early preterm birth. American College of Obstetricians and Gynecologists. http://www.acog.org/~/media/For%20Patients/faq173.pdf?dmc=1&ts=20130215T1057545204. Accessed Feb. 15, 2013.
- Frequently asked questions. Pregnancy FAQ087. Preterm labor. American College of Obstetricians and Gynecologists. http://www.acog.org/~/media/For%20Patients/faq087.pdf?dmc=1&ts=20130131T1258459154. Accessed Jan. 31, 2013.
- Sanchez-Ramos L, et al. Fetal fibronectin as a short-term predictor of preterm birth in symptomatic patients: A meta-analysis. Obstetrics and Gynecology. 2009;114:631.
- DeFranco EA, et al. Improving the screening accuracy for preterm labor: Is the combination of fetal fibronectin and cervical length in symptomatic patients a useful predictor of preterm birth? American Journal of Obstetrics and Gynecology. In press. Accessed Feb. 15, 2013.
- Berghella V. Transvaginal ultrasound assessment of the cervix and prediction of spontaneous preterm birth. http://www.uptodate.com/home. Accessed Feb. 15, 2013.
- Healthy pregnancy: Staying healthy and safe. The National Women's Health Information Center. http://www.womenshealth.gov/pregnancy/you-are-pregnant/staying-healthy-safe.cfm. Accessed Feb. 15, 2013.
- American College of Obstetricians and Gynecologists. Your Pregnancy and Childbirth Month to Month. 5th ed. Washington, D.C.: American College of Obstetricians and Gynecologists; 2010:363.
- Harms RW (expert opinion). Mayo Clinic, Rochester, Minn. Feb. 15, 2013.


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