Article Text
Abstract
Antenatal corticosteroids should be administered to women between 24- and 34-week gestation with any symptoms of imminent delivery. In asymptomatic women, fetal fibronectin (fFN) testing is an excellent predictive marker of preterm birth (PTB). It has been shown to have a negative predictive value of >99% in women at <30-week gestation. However, the use of steroids in asymptomatic high risk women is unclear.
Aim To evaluate whether, in clinical practice, the screening of high-risk asymptomatic women with fFN targets prophylactic steroid use appropriately.
Method Prospective analysis of asymptomatic women at high risk of PTB between 22- and 32+6-week gestation, who presented to a Preterm clinic March 2008 to September 2009.
Results 46/271 women were positive for fFN; 20/46 (43%) delivered preterm and 9/20 (48%) of PTB babies received prophylactic steroids at time of screening. Steroid to delivery ranged from 0 to 76 days. Of those screening positive and delivering preterm, 13/20 (65%) delivered within 4 weeks of screening.
Only 20% of fFN negative women (46/226) delivered preterm. None of the negative women received steroids as a result of screening. No woman delivered within 4 weeks of screening.
Conclusion That 65% of PTBs who screened positive delivered within 4 weeks of screening demonstrates that fFN may direct appropriate prophylactic steroid use. fFN negative women did not deliver within 1 month of testing; fFN may thus prevent the inappropriate use of steroids in screen-negative high risk women. The clinical value of prophylactic steroids used in this manner needs further evaluation.