1. Which Factors Contribute to False-Positive, False-Negative, and Invalid Results in Fetal Fibronectin Testing in Women with Symptoms of Preterm Labor?
- Author
-
Bruijn MM, Hermans FJ, Vis JY, Wilms FF, Oudijk MA, Kwee A, Porath MM, Oei G, Scheepers HC, Spaanderman ME, Bloemenkamp KW, Haak MC, Bolte AC, Vandenbussche FP, Woiski MD, Bax CJ, Cornette JM, Duvekot JJ, Bijvank BW, van Eyck J, Franssen MT, Sollie KM, van der Post JA, Bossuyt PM, Kok M, Mol BW, and van Baaren GJ
- Subjects
- Adult, Coitus, Endosonography, False Negative Reactions, False Positive Reactions, Female, Gestational Age, Humans, Obstetric Labor, Premature metabolism, Pregnancy, Risk Factors, Soaps, Uterine Hemorrhage metabolism, Young Adult, Fibronectins analysis, Obstetric Labor, Premature diagnosis, Vagina chemistry
- Abstract
Objective We assessed the influence of external factors on false-positive, false-negative, and invalid fibronectin results in the prediction of spontaneous delivery within 7 days. Methods We studied symptomatic women between 24 and 34 weeks' gestational age. We performed uni- and multivariable logistic regression to estimate the effect of external factors (vaginal soap, digital examination, transvaginal sonography, sexual intercourse, vaginal bleeding) on the risk of false-positive, false-negative, and invalid results, using spontaneous delivery within 7 days as the outcome. Results Out of 708 women, 237 (33%) had a false-positive result; none of the factors showed a significant association. Vaginal bleeding increased the proportion of positive fetal fibronectin (fFN) results, but was significantly associated with a lower risk of false-positive test results (odds ratio [OR], 0.22; 95% confidence intervals [CI], 0.12-0.39). Ten women (1%) had a false-negative result. None of the investigated factors was significantly associated with a significantly higher risk of false-negative results. Twenty-one tests (3%) were invalid; only vaginal bleeding showed a significant association (OR, 4.5; 95% CI, 1.7-12). Conclusion The effect of external factors on the performance of qualitative fFN testing is limited, with vaginal bleeding as the only factor that reduces its validity., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)
- Published
- 2017
- Full Text
- View/download PDF