Cervical phosphorylated insulin-like growth factor binding protein-1 for the prediction of preterm delivery in symptomatic cases with intact membranes.

AIM: This prospective, observational study was an attempt to evaluate whether a positive cervical phosphorylated insulin-like growth factor binding protein-1 admission test in women with signs and symptoms of preterm labor (PTL) may be useful in the prediction of women who will deliver prematurely.

METHODS: Pregnant women with confirmed gestational age between 24 and 37 weeks' gestation with <3 cm cervical dilatation and intact membranes were included in the study. Prior to digital examination, a sterile speculum examination was performed using a dacron swab rotated in the external cervical os for 15 s. The test was based on immunochromatographic qualitative analysis of cervical phosphorylated insulin-like growth factor binding protein-1. Test (+) and (-) cases were evaluated in terms of maternal demographic characteristics and neonatal outcomes.

RESULTS: A total of 68 cases were enrolled in the study. There were no statistically significant differences between test (+) and (-) groups, in terms of maternal characteristics or adverse neonatal outcomes. However, cases with + test had high Bishop scores on admission (P = 0.01) and gestational age at delivery (P = 0.003). For deliveries within 7 days of admission, the strongest predictors were test positivity (RR:24,%95CI:2.8-204, P < 0.0001) and Bishop score (RR:1.3, %95CI: 1.0-1.6, P = 0.03). For deliveries <34 weeks' gestation, the test had a sensitivity, specificity, positive predictive values, negative predictive values, +likelihood ratios and -likelihood ratios of 70%, 74%, 48%, 88, 2.8 and 0.39, respectively.

CONCLUSION: Among women with signs and symptoms of PTL, the high negative predictive value of this test to predict the PTL <34 weeks' gestation as well as within 7 days of delivery may be of value in the reassurance of patients, avoiding unnecessary medical interventions.