Investigating Relationship between Saliva Estriol to Progesterone Ratio and Preterm Delivery

Preterm delivery is a serious obstetrical problem and leading cause of perinatal mortality in the non-anomalous infant. Therefore, the suitable screen test to determine high risk women is necessary. Salivary estriol to progesterone ratio changes during parturition. Therefore, using non-invasive, non-stress, and easy assessment of salivary estriol to progesterone ratio can be a reliable test for predicting preterm delivery. The present study aimed to investigate relationship between salivary estriol to progesterone ratio and preterm delivery. This was an analytical case -control study conducted on 76 women at 28-34 weeks of pregnancy referred to Ahvaz Imam Hospital in 2009. The saliva samples of 38 women with preterm labor symptoms and 42 women with normal pregnancy between 9 am-8 pm were collected and frozen at -20 degrees C. Then, the salivary estriol to progesterone ratios were measured using Eliza method. The data were analyzed with SPSS version 18 using paired T test and Chi-square tests. The results showed significant difference in the mean estriol (p= 0.01), progesterone (p= 0.001), and estriol to progesterone ratio between the two groups (p= 0.001). Our findings showed that salivary estriol to progesterone ratio increased in preterm delivery; thus, it can be a good predictor of preterm delivery.