"Blind" vaginal fetal fibronectin as a predictor of spontaneous preterm delivery.
OBJECTIVE
To assess the accuracy of vaginal fetal fibronectin sampling without use of a sterile speculum examination as a screening test for predicting spontaneous preterm birth.


METHODS
A historical cohort of patients who were followed up with serial fetal fibronectin testing between 1998 and 2001 was identified. All patients were considered to be at high risk for preterm delivery and were screened with fetal fibronectin testing without using a speculum at 2- to 3-week intervals from 22 weeks to 32 weeks of gestation. Charts were reviewed for fetal fibronectin results and pregnancy outcome data. Groups were compared using chi(2) analysis or Fisher exact test with significance defined as P < .05.


RESULTS
A total of 1,396 fetal fibronectin tests from 416 pregnancies were performed via the "blind" sampling technique. Overall, 24.9% of pregnancies delivered spontaneously before 37 weeks; 9.1% delivered spontaneously before 34 weeks. For delivery before 34 weeks of gestation, the test had a sensitivity of 44.7%, a specificity of 88.4%, a positive predictive value of 27.9%, and a negative predictive value of 94.1%. For delivery within 14 and 21 days of a single fetal fibronectin assessment, the test had a sensitivity of 52% and 45.5%, a specificity of 94.5% and 94.9%, a positive predictive value of 14.6% and 22.5%, and a negative predictive value of 99.1% and 98.2%, respectively.


CONCLUSIONS
"Blind" vaginal fetal fibronectin sampling has high negative predictive values and specificities in predicting spontaneous preterm birth.


METHODS
II-2.
Roman
Ashley S
AS
Department of Obstetrics and Gynecology, New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA. achapinsmith@aol.com
Koklanaris
Nikki
N
Paidas
Michael J
MJ
Mulholland
Jeanine
J
Levitz
Mortimer
M
Rebarber
Andrei
A
D000328:Adult; D015415:Biomarkers / Q000032:analysis; D015331:Cohort Studies; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005353:Fibronectins / Q000032:analysis* / Q000378:metabolism; D005500:Follow-Up Studies; D005865:Gestational Age; D006023:Glycoproteins / Q000032:analysis* / Q000378:metabolism; D006801:Humans; D007752:Obstetric Labor, Premature / Q000175:diagnosis* / Q000453:epidemiology; D010298:Parity; D011237:Predictive Value of Tests; D011247:Pregnancy; D011256:Pregnancy Outcome; D011295:Prenatal Care / Q000379:methods; D011336:Probability; D012189:Retrospective Studies; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D014626:Vaginal Smears
D015415:Biomarkers; C403421:FFN protein, human; D005353:Fibronectins; D006023:Glycoproteins