Geetha Damodaran K.1 , Lalithambika Karunakaran2 , Sreedevi N.3 , Rajesh K.M.4
BACKGROUND Presently used clinical and ultrasound diagnostic criteria for predicting preterm labour (PTL) have limitations. Instead an objective diagnostic marker will be more appropriate. METHODS Pregnant women during 24 – 35 weeks of gestation who attended T.D. Medical College for antenatal check-up were included in this prospective observational study as per inclusion and exclusion criteria with informed consent. The cervicovaginal lavage fFN was assayed by ELISA and total protein (TP) by photometric Biuret method. To counter dilutional errors, fFN is expressed in ng / 0.1 gram of TP in CVL. The type of delivery of enrolled subjects was recorded as preterm (14/216) and term (202/216). MedCalc trial version 18.2 was used for statistical analysis. RESULTS Reference interval of fFn in CVL ranged from 6.2 to 69 ng / 0.1 g TP. The best diagnostic cut off value of CVL fFN during 24 – 35 weeks of gestation to predict PTL in asymptomatic pregnant women is 63 ng / 0.1 g TP (AUC: 0.891; P: <0.0001) with a sensitivity of 79 and specificity of 97%. CONCLUSIONS The CVL fFN assay is useful as a predictive marker of PTL. Its high negative predictive value will help in reducing unnecessary hospital admissions. Merit of this study is reduction in dilutional inaccuracies by expressing fFN as ng per 0.1 g of TP in CVL.
