The utility of fFN for the prediction of preterm birth in twin gestations.
OBJECTIVE
To determine the sensitivity, specificity, and positive predictive value (PPV) of fetal fibronectin (fFN) and to determine its usefulness, in conjunction with selected other clinical assessment measures, in the prediction of preterm birth for women with twin gestations.


METHODS
A prospective, descriptive, longitudinal design.


METHODS
An obstetrical high-risk clinic that received patient referrals from several surrounding communities in central Texas.


METHODS
Forty-eight women identified with twin gestations prior to the 22nd week of pregnancy; primarily of Hispanic ethnicity.


METHODS
A substantial number of outcome variables were assessed in this study. In the present report, data derived from weekly assessments for the identification of the presence of fFN, the diagnosis of bacterial vaginosis, and the measurement of cervical length were reviewed for their relationship to prematurity, birth weight, birth weight discordancy and placental chorionicity.


RESULTS
The relative risk of birth prior to 35 weeks gestation, fetal death, or discordance of twin birth weights of greater than 20% was 2.22 (CI: 1.09, 4.55, P < 0.015) when fFN was found to be positive at any weekly testing after 22 to 24 weeks gestation (sensitivity 76.82%, specificity 58.33%, PPV 66.7%). The presence of fFN was most highly predictive of preterm birth when performed during the 24th to 28th gestational week. Shorter cervical lengths were highly correlated with preterm birth (r = -0.6). An association between bacterial vaginosis and preterm birth was not demonstrated in this sample.


CONCLUSIONS
Sampling for the presence of fetal fibronectin can be easily accomplished by RNs in labor triage units and by advanced practice nurses in outpatient settings. The identification of fFN, particularly during the 24 to 28 weeks gestational time frame, is highly predictive of preterm birth, and particularly so for women with twin gestations.
Ruiz
R Jeanne
RJ
School of Nursing, University of Texas Health Science Center at San Antonio, Universal City 78148, USA. ruizr@uthscsa.edu
Fullerton
Judith
J
Brown
Charles E L
CE
D000293:Adolescent; D000328:Adult; D000886:Anthropometry / Q000379:methods; D001724:Birth Weight; D002584:Cervix Uteri / Q000737:chemistry* / Q000473:pathology; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods / Q000592:standards; D005260:Female; D005353:Fibronectins; D005865:Gestational Age; D006023:Glycoproteins / Q000032:analysis*; D006630:Hispanic or Latino; D006801:Humans; D024802:Nurse's Role; D007752:Obstetric Labor, Premature / Q000175:diagnosis* / Q000208:ethnology / Q000209:etiology; D011237:Predictive Value of Tests; D011247:Pregnancy; D011256:Pregnancy Outcome; D018566:Pregnancy, High-Risk; D011446:Prospective Studies; D012306:Risk; D013781:Texas / Q000453:epidemiology; D014427:Twins; D014626:Vaginal Smears / Q000379:methods / Q000592:standards*; D016585:Vaginosis, Bacterial / Q000150:complications
C403421:FFN protein, human; D005353:Fibronectins; D006023:Glycoproteins