Prediction of Preterm Delivery: A Pilot Study on the Use of Rapid Phosphorylated Insulin-like Growth Factor-binding Protein 1 Test

Abstract

Objective: This was a pilot study to determine whether the rapid phosphorylated insulin-like growth factor-binding protein 1 (phIGFBP-1) bedside test can help to predict preterm delivery in women who presented with symptoms of threatened preterm labour in our local population in Hong Kong.
Methods: This prospective cohort study was conducted in a tertiary obstetrics and gynaecology unit. Pregnant women with a singleton pregnancy and intact membrane who presented with symptoms of threatened preterm labour between 24 and 34 weeks’ gestation, from July 2013 to May 2014, were recruited. Cervical samples were taken for
rapid phIGFBP-1 bedside testing from eligible consenting patients. Sensitivity, specificity, negative predictive value, and positive predictive value of the rapid phIGFBP-1 bedside test to predict preterm delivery within 48 hours, 7 days, 14 days, as well as at <34 and <37 weeks’ gestation were measured.
Results: A total of 39 women were recruited. Of 19 (49%) who had a positive result for the phIGFBP-1 test, three (16%) delivered within 7 days. A negative phIGFBP-1 test was confirmed in 20 (51%) women of whom two delivered within 7 days and one within 48 hours. The negative predictive value for predicting delivery within 7 days and 48 hours was 90% and 95%, respectively. The delivery outcome for women with a positive and those with a negative phIGFBP-1 result showed no statistical difference.
Conclusion: The high negative predictive value in this pilot study was similar to that in other studies.