I. Hospital admissions II. Intervention result in relation to FFN

III. Gestational age In relation to FFN IV. In relation to delivery

V. Relation of delivery to VI. Relation to Hospital Days gestation in weeks

Prediction of Preterm Labor by Fetal Fibronectin in Multiple Gestations Afshan Samad M.B.B.S., Chad Strittmater M.D.

Department of Obstetrics & GynecologySisters of Charity Hospital, 2157 Main Street, Buffalo, NY 14214

FFN+FFN-

0

10

20

30

40

P = 0.026*

Sa

mp

le C

oll

ec

tio

n

FFN+FFN-

0

10

20

30

40

De

liv

ery

We

ek

P = 0.0001***

0

2

4

6

8

P = 0.0091**Hosp

ital D

ays

Del.0-7 Days.

Del.0-14 Days.

Total

FFN + 6 5 11/24

FFN - 1 0 1/51

Total 7 5 12

Sensitivity : 15/30 = 50% Specificity : 36/45 = 80% PPV : 15/24 = 62% NPV : 36/51 = 70.59% Prevalence: 15/75 = 20%

FFN + Mean + SD (SEM)

FFN – Mean + SD(SEM)

P value

Gravidity 2.83 + 2.7 (0.557) 2.73 + 2.0(0.292) NSParity 1.16 + 2.0 (0.428) 1.03 + 1.3(0.189) NSGA @ FFN test 27.21 + 3.7 (0.775) 29.24+2.8 (0.395) 0.0258*GA @ Delivery 31.54 + 3.76 (0.768) 35.20 + 2.21(0.310) 0.0001***Hospital stay 5.16 + 6.53 (1.333) 1.176+ 3.7(0.522) 0.0091**

INTRODUCTION: Fetal fibronectin (Figure 1) is glycoprotein produced by chorionic membranes and is localized to deciduas basalis adjacent to intervillous space. Adhesion molecule between chorionic membrane and the maternal deciduas. Normally present in cervicovaginal secretions till 22 wks but never found from 24 to 34 weeks unless patient is in preterm labor. The aim of this study was to determine the accuracy in predicting preterm deliveries.

DEMOGRAPHICS: Patients who had FFN test at Sister’s Labor & Delivery from June 2005–June 2008 charts were analyzed. Results of the test were notified as either “POSITIVE” or “NEGATIVE”. FFN test is performed by immunochromatographic assay. The utility of FFN rests primarily with NPV 99.5% @ 7days and 99.2% @ 14 days.PPV value @ 13-30%.

SAMPLE COLLECTION Using unlubricated speculum from post fornix or external cervical os.Test results Positive >50ng/mLNegative <50ng/mL

CHARTS REVIEWED: Total Number of Charts Reviewed 337 Number of charts meeting criteria 75 FFN NEGATIVE 51 FFN POSITIVE 24

Del. <34 wks.

Del. >34 wks.

Total

FFN + 15 9 24

FFN - 15 36 51

Total 30 45 75

FFN + FFN -0

20

40

60

80< 34 weeks> 34 weeks

To

tal C

ases

%

Hospital Admissions0

20

40

60

80FFN +

FFN -

Tota

l Cas

es %

CONCLUSIONS:1. FFN test is useful in identifying patients with multiple gestation not at risk for preterm labor within 7-14 days of negative FFN (NPV of 98%).2. Community physicians at Sisters of Charity Health have extrapolated FFN data from singletons to multiple gestation pregnancies with similar outcome.3. Negative tests strongly correlates with decreased admissions, length of stay and tocolytics.4. PPV in multiple gestation is 25-45% within 7-14 days which is a higher predictive value in multiple gestation compared to a singleton i.e a positive test means something. Consider clinical assessment and previous history of preterm labor.

PPV within 7 days: 25%PPV within 14 days: 45%NPV within 7 days: 98%NPV within 14 days: 98%

Tocolysis Betamethasone0

20

40

60

80

100

To

tal C

as

es

%

REFERENCES:1. The utility of FFN for the prediction of preterm birth in twin gestations.JOGNN,Vol33, July/August 2004.2. Accuracy of Fetal Fibronectin to predict preterm birth in twin gestation with symptoms of labor. Obstetrics and Gynecology, Vol 109(5), May 2007.3. Fetal Fibronectin as a predictor of preterm birth in quadruplet pregnancies.American Journal of Obstetrics and Gynecology, Vol 191(6),Supplement, December 2004.4. Prediction of preterm delivery in twin pregnancy: a prospective, observational study of cervical length and fetal fibronectin testing.Ultrasound Obstet Gynecology, Vol 23, 2004.5. Early prediction of preterm birth for singleton, twin, and triplet pregnancies. European Journal of Obstetrics and Gynecolgy and reproductive biology.Vol 131, 2007.6. ACOG practice bulletin #31, Oct 2001.7. ACOG Practice bulletin #43,May 2003. 8. Uptodate 2008.9. Detection of FFN in twin pregnancies in relation to gestational age. Sao Paulo Medical Journal.Vol. 117, May 1999.

ACKNOWLEDGEMENTS: Dr.Judine Davis, K.Bernacki, Medical Records

Figure 1

Objective: To determine accuracy of predicting preterm deliveries in multiple gestation and study the impact of FFN on hospital admissions and interventions. This study was done to test sensitivity, specificity, positive predictive value and negative predictive value of FFN in predicting delivery within 14 days of testing at Sisters of Charity Hospital.Inclusion Criteria: Multiple pregnancy between 24-34 weeks gestation regardless of age, race and parity. Preterm contractions at least 6/hr.Intact membranes.Exclusion Criteria: Vaginal bleeding. Pelvic exam or sexual intercourse 24 h prior. Ruptured membranes. Cervical dilation > 3 cm. Cervical length by vaginal sono < 25mm, cervical cerclage.

Table 1 Table 2RESULTS: