Fetal fibronectin testing for reducing the risk of preterm birth

  • Review
  • Intervention




Fetal fibronectin (FFN) is an extracellular matrix glycoprotein localized at the maternal-fetal interface of the amniotic membranes, between chorion and decidua, where it is concentrated in this area between decidua and trophoblast. In normal conditions, FFN is found at very low levels in cervico-vaginal secretions. Levels greater than or equal to 50 ng/mL at or after 22 weeks have been associated with an increased risk of spontaneous preterm birth. In fact, FFN is one of the best predictors of preterm birth in all populations studied so far, and can help selecting which women are at significant risk for preterm birth.


To assess the effectiveness of management based on knowledge of FFN testing results for preventing preterm birth.

Search methods

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (January 2008), MEDLINE (1966 to December 2007) and all references in identified articles.

Selection criteria

Randomized controlled trials of pregnant women between the gestational ages of 22 and 34 weeks screened with FFN for risk of preterm birth. Studies included are based exclusively on knowledge of FFN results versus no such knowledge, and we have excluded studies including women with only positive or only negative FFN results.

Data collection and analysis

All four authors assessed studies for inclusion and quality and extracted data.

Main results

We identified 13 trials, of which five were eligible for inclusion. The five included studies randomized 474 women, of which 235 were randomized to knowledge and 249 to no knowledge of FFN.

Preterm birth less than 37 weeks was significantly decreased with management based on knowledge of FFN results (15.6%) versus controls without such knowledge (28.6%; risk ratio 0.54; 95% confidence interval 0.34 to 0.87). All other outcomes for which there were available data (preterm birth at less than 34, 32, or 28 weeks; gestational age at delivery; birthweight less than 2500 grams; perinatal death; maternal hospitalization; tocolysis; steroids for fetal lung maturity; and time to evaluate) were similar in the two groups. No other maternal or neonatal outcome was available for meaningful analysis.

Authors' conclusions

Although FFN is commonly used in labor and delivery units to help in the management of women with symptoms of preterm labor, currently there is not sufficient evidence to recommend its use. Since this review found an association between knowledge of FFN results and a lower incidence of preterm birth before 37 weeks, further research should be encouraged.



胎兒纖維結合素(Fetal fibronectin)檢測以減少早產風險

胎兒纖維結合素(FFN)是一種細胞外基質糖蛋白,位於母親和胎兒的羊膜介面,在絨毛膜(chorion)和蛻膜(decidua)之間,在蛻膜和滋養母細胞之間的濃度最高。正常情況下,子宮頸陰道分泌物的FFN值相當低。懷孕22週之後,FFN值大於等於5 g/mL 與自發性早產風險增加有關。事實上,FFN是迄今對各族群的所有研究中,最佳的早產預測因子,有助於篩選哪些婦女有明顯早產風險。




我們搜尋Cochrane Pregnancy和Childbirth Group's Trials Register (2008年1月)、MEDLINE (1966年2007年12月)以及相關文獻所有的參考資料。


針對妊娠22 – 34週之孕婦使用FFN篩檢檢測早產風險的隨機控制試驗(Randomized controlled trials)。研究之納入係根據是否知道FFN結果,排除只有紀錄FFN陽性或陰性的研究。




我們檢視13篇試驗,其中5篇適合納入。這5篇研究隨機分派474名婦女,其中235名隨機分派為知道FFN結果,其他249人則不知FFN結果。根據FFN結果來進行處置者,37週前早產比率顯著降低(15.6%),對照組則是28.6% (RR為0.54; 95% CI為0.34 – 0.87)。兩組的其他資料(28、32、34週以前之早產;生產時的妊娠週數;出生體重小於2500公克;週產期死亡;母親住院;安胎;使用類固醇幫助胎兒肺部成熟;進行評估的時間)則相似。其他沒有有關母親或嬰兒的結果可供有意義分析。




此翻譯計畫由臺灣國家衛生研究院(National Health Research Institutes, Taiwan)統籌。


胎兒纖維結合素檢測以減少早產風險: 37週前早產是新生兒死亡和生病的主因。雖然多數婦女在早產前有宮縮等症狀,大部份婦女還是在足月時(大於或等於37週)生產。胎兒纖維結合素這項檢測,藉由測量陰道和/或子宮頸的分泌物,可以確認哪些有早產症狀的婦女比較有早產風險。此次回顧5篇控制研究隨機分組474名婦女,並未發現有足夠證據支持例行性使用胎兒纖維結合素檢測以對有早產症狀的婦女進行處置。應該鼓勵進行後續的研究。

Plain language summary

Fetal fibronectin testing for reducing the risk of preterm birth

Preterm birth before 37 weeks is the main cause of death and sickness for newborn infants. While most women have preterm labor symptoms such as contractions before having a preterm birth, most such women with symptoms deliver at term (greater than or equal to 37 weeks). Fetal fibronectin is a test that can identify the women with symptoms of preterm labor most at risk for preterm birth by measuring the level in secretions from the vagina and/or cervix. This review of five controlled studies that randomised 474 pregnant women did not find enough evidence to support or refute the use of the fetal fibronectin test for the management of women with symptoms of preterm labor. Further research should be encouraged.