Impact of the fetal fibronectin assay on admissions for preterm labor

OBJECTIVE: The aim of the study was to determine whether use of the fetal f ibronectin assay would decrease the number of admissions to labor and deliv ery for diagnosis and treatment of preterm labor. STUDY DESIGN: A prospective cohort design was used to compare preterm labor admissions during a 12-month period of fetal fibronectin assay use (study) against a baseline period before fetal fibronectin assay was implemented a s standard protocol. Patients coming to the physician's office or hospital with signs and symptoms of preterm labor had a sample obtained for fetal fi bronectin assay per labeling criteria. Comparisons were made with the Mann- Whitney U test, independent Student t test,;chi(2) test, and Fisher exact t est. P <.05 was considered significant. RESULTS: There was no difference noted in the number of deliveries between the baseline and study years. During the study year 251 of 330 patients eva luated for preterm labor met study criteria and had the fetal fibronectin a ssay completed. Eight patients did not have fetal fibronectin assay results available because of specimen handling errors, leaving 243 subjects availa ble for study. Compared with the baseline year, the study year had signific antly fewer admissions for preterm labor, preterm labor admissions per pati ent, and prescriptions written for tocolytic agents. In addition, the lengt h of stay per admitted patient was significantly reduced. The study populat ion had no differences in neonatal outcomes from the baseline population in terms of deliveries at <35.0 weeks' gestation, number of admissions to the neonatal intensive care unit, neonatal intensive care unit length of stay, or days of ventilatory support per patient admitted to the neonatal intens ive care unit. CONCLUSIONS: Use of the fetal fibronectin assay resulted in significantly r educed preterm labor admissions, length of stay, and prescriptions for toco lytic agents. No negative impact on neonatal outcomes was observed. Reducti ons in admissions for preterm labor and in charges per admission resulted i n approximately $486,000 saved during the study period. A trend toward incr eased corticosteroid administration (for neonates ultimately admitted to th e neonatal intensive care unit) was noted.