Fetal fibronectin: the impact of a rapid test on the treatment of women with preterm labor symptoms. Prospective randomized controlled trial of fetal fibronectin on preterm labor management in a tertiary care center. Does knowledge of cervical length and fetal fibronectin affect management of women with threatened preterm labor? A randomized trial. Does fetal fibronectin use in the diagnosis of preterm labor affect physician behavior and health care costs? A randomized trial.
The purpose of this study was to determine whether knowledge of the results of a rapid fetal fibronectin test affects treatment decisions during the evaluation and treatment of possible preterm labor. Previous observational studies have suggested that a negative test might help to avoid unnecessary intervention.
                This was a randomized study of women who were between 24 weeks and 34 weeks 6 days of gestation with symptoms of preterm labor and who were seen in three community hospitals. A rapid fetal fibronectin test was performed on all subjects. Patients were assigned randomly to a group whose results were known to physician or to a group whose results were not known. Treatment decisions were at the discretion of the physician.
                One hundred eight samples were collected between September 2000 and December 2001. There were 10 positive fetal fibronectin tests. The overall prevalence of delivery within 2 weeks for the study population was 2.8%. For women who had negative fetal fibronectin test results, the hospital stay was not significantly shorter when the result was known (6.8 hours) than when it was not known (8.1 hours, P =.35). However, when the physician knew the fetal fibronectin status of women with a negative test result who were observed for >6 hours, the hospital stay was shortened 40%, to 22.7 hours from 37.8 hours (P =.04).
                Fetal fibronectin testing may be able to supplement clinical judgment in the evaluation of the condition of patients with symptoms of preterm labor. The greatest benefit of fetal fibronectin testing might be for the patient whom the physician judges to be at high risk for imminent delivery. In such patients, the knowledge of a negative fetal fibronectin may shorten the hospital stay. The purpose of this study was to investigate the effect of the rapid fetal fibronectin on the length of hospital stay and the use of preterm labor interventions in a tertiary care center.
                Women who were seen in the Labor and Delivery Unit with symptoms of preterm labor were assigned randomly to receive fetal fibronectin (n=46 women) or to preterm labor management without fetal fibronectin (n=51 women). Physicians were not blinded to the result; groups were compared.
                There was no difference between groups in demographic or obstetric characteristics, the hours spent in labor and delivery, the number of women who were admitted to the antepartum service, the length of stay, or medical interventions. When the results for women with a negative fetal fibronectin test were compared to women with a positive fetal fibronectin test, a significant difference was found in admissions to the antepartum service (P=.032) and the length of stay (P=.008).
                A negative fetal fibronectin test was associated with fewer admissions to the antepartum ward and a shorter length of stay. The purpose of this study was to estimate the effect of sonographic cervical length (CL) and fetal fibronectin (FFN) on length of evaluation and outcomes in women with preterm labor (PTL).
                Women with threatened PTL were randomized to either a knowledge group (results of CL and FFN available and used according to study protocol), or a standard group (blinded to CL and FFN). Primary outcome was length of evaluation in triage.
                One hundred women were randomized. There was no significant difference between groups in length of evaluation, but in women with CL > or = 30 mm, the mean time for evaluation was significantly shorter in the knowledge group (1:58 h +/- 0:50 vs 2:53 h +/- 0:50, P = .004). Incidence of spontaneous preterm birth (SPTB) in the knowledge group was significantly reduced (13.0 vs 36.2%, P = .01).
                The knowledge of CL and FFN was associated with reduction in length of evaluation in women with CL > or = 30 mm and in incidence of SPTB in all women with PTL. The purpose of this study was to determine whether a knowledge of fetal fibronectin results affects patient treatment and health care costs.
                Women between 24 and 34 weeks of gestation with a singleton pregnancy and preterm uterine contractions were eligible for enrollment. Once informed consent was given, a fetal fibronectin specimen was obtained, and women were assigned randomly into 2 groups. In 1 group, results of the fetal fibronectin test were available; in the other group, results were not available. The use of inpatient and outpatient health care resources subsequent to enrollment was ascertained through the use of medical records, hospital billing data, and patient interviews. This study was powered to allow the detection in the fetal fibronectin group of a 20% reduction in total health care-related costs.
                The 2 groups were similar with respect to maternal age, parity, race, cervical examination at admission, and estimated gestational age at enrollment and at delivery. Women who did not have fetal fibronectin results available were no different than those women who did with respect to initial length of labor and delivery observation (median, 4 hours vs 3 hours), hospital admission (28% vs 26%), tocolysis (18% vs 16%), cessation of work (27% vs 26%), or total health care-related costs (log mean +/- SD, 7.6 +/- 1.2 vs 7.5 +/- 1.1).
                In this study population, the use of fetal fibronectin did not affect physician behavior or health care costs related to preterm contractions.
Although FFN is commonly used in labor and delivery units to help in the management of women with symptoms of preterm labor, currently there is not sufficient evidence to recommend its use. Since this review found an association between knowledge of FFN results and a lower incidence of preterm birth before 37 weeks, further research should be encouraged.