[Preterm labor: Reproducibility of detection test of PAMG-1 before and after digital examination, and transvaginal ultrasound cervical length].

OBJECTIVES: With current diagnostic resources, it is impossible to predict if a patient consulting in the obstetrics emergencies with symptoms of preterm labor, preterm delivery or not. A novel test for the detection of time to spontaneous preterm delivery was developed and would predict imminent delivery in 7 or 14 days from the time of testing. The diagnostic performances of detection test of PAMG-1 have been validated before digital examination. However digital examination is usually made in first line. The objective of this study was to assess the reproducibility of these diagnostic performances after digital examination and transvaginal ultrasound cervical length.

METHODS: A prospective and observational study was conducted in a level 3 maternity (University Hospital of Saint-Etienne), from June 2013 to January 2014. Patients consulted in the obstetrics emergencies for threatened preterm birth between 24-34 weeks were enrolled with written and signed consent. Reproducibility of this test was assessed after digital examination, transvaginal ultrasound cervical length and a long time after all investigations.

RESULTS: Forty-one patients were included in our study. Average gestational age was 29 weeks, digital examination was changed in 36 patients, whereas cervical length was less than 26mm for only 17 patients. In our study, 100% of tests results remain negative or positive after digital examination and 95,1% after transvaginal ultrasound. Our results confirmed this excellent specificity (97.5% [IC 95%; 86.8-99.9]) and negative predictive value (97.5% [IC 95%; 86.8-99.9]).

CONCLUSION: This work allowed to demonstrate the reproducibility of detection test of PAMG-1 after a digital examination. An initial management with detection test of PAMG-1 could allow reducing the rate of unnecessary hospitalization.