accompanied by a high false-positive rate. As many as
50% of subjects enrolled in the placebo arms of prospective,
controlled trials of tocolytic medications will be
delivered after 37 weeks.’ These false diagnoses result
in unnecessary and potentially hazardous treatment for
thousands of women annually. An improved method of
early diagnosis would be a significant advance.
Oncofetal fibronectin is an extracellular matrix pro-
From The Ohio State University,,” the University of Colorado Health
Science Center,’ the University of Southern California,’ Oregon
Health Sciences University,* the University of British Columbia,” and
Adeza Biomedical.”
Received for publication August I5, 1994; revised December 1,
1994; accepted December 5, 1994.
Reprints not available from the authors.
Copyright 0 1995 by Mosby-Year Book, Inc.
0002-9378/95 $3.00 + 0 6/l/62541
tein that is normally found in the fetal membranes and
decidua. As the gestational sac implants and attaches to
the interior of the uterus in the first half of pregnancy,
fetal fibronectin is normally found in cervicovaginal
fluid. The presence of fetal fibronectin in the cervix or
vagina after the twentieth week is abnormal and may
indicate disruption of the attachment of the membranes
to the decidua.” In contrast to other potential predictors
of premature delivery, such as obstetric history or
frequent uterine contractions, the presence of fetal
fibronectin in cervicovaginal fluid provides direct evidence
of pathologic changes at the interface of fetal and
maternal tissues. The finding of fetal fibronectin in the
cervix and vagina after 20 weeks has therefore been
investigated as a possible marker for risk of preterm
birth.
Lockwood et