A comparison of speculum and nonspeculum collection of cervicovaginal specimens for fetal fibronectin testing.

Abstract

Current recommendations include the use of a vaginal speculum for fetal fibronectin specimen collection. This article evaluates the equivalency of nonspeculum methods for collecting fetal fibronectin specimens. Two separate prospective studies of patients more than 22 weeks' gestation were performed at 2 institutions with similar hypotheses and methods. Two sequential specimens were collected on each patient: 1 with speculum and 1 with the nonspeculum method. The order of collection was reversed or randomized in both studies. Two alternative nonspeculum collection methods are described. The 2 study sample sizes were 169 and 31. Comparison of the fetal fibronectin test results between the speculum and nonspeculum methods demonstrated greater than 95% agreement with an intraclass Kappa coefficient greater than 0.85 in both studies. The order of collection did not result in significantly different fetal fibronectin averages. These studies demonstrate that there is excellent agreement between fetal fibronectin results obtained by speculum and nonspeculum collection methods.