The Role of Salivary Progesterone in Predicting Women At-Risk of Preterm Delivery

Abstract

Background: Vaginal fetal fibronectin assay has been used as a gold standard biomarker for the prediction of preterm birth especially among symptomatic pregnant women with relatively good sensitivity and high specificity. However, recent evidence is emerging that salivary progesterone assay can be used to predict preterm birth. Methodology: A cohort study was used to assess the predictive values of salivary progesterone in women at-risk for preterm delivery at a tertiary hospital in Kano – Nigeria. Salivary samples were collected for progesterone level assay between 28-32weeks of gestation among 135 asymptomatic pregnant women. The study participants were followed up and the gestational age of delivery was determined and receiver operator characteristic curve was plotted to determine the predictive cut off value for salivary progesterone. Results: The mean salivary progesterone was found to be 854.24 ± 192.25pg/ml and 1599.06 ± 226.09pg/ml for those who had preterm and term deliveries respectively. There was a statistically significant difference in the mean salivary progesterone between the two groups. At a cut off value of 1253.3pg/ml, salivary progesterone was found to have a Sensitivity of 100%, Specificity of 90.8%, Positive Predictive Value of 85.7 and Negative Predictive Value of 100%. Conclusion: This study found salivary progesterone quantitative assay to be useful in predicting preterm birth among women at-risk, with high diagnostic accuracy. Therefore, it can be used as screening tool for women at risk of preterm delivery.

Key words: Salivary; Progesterone; Assay; Preterm