Abstract
Objectives: This study was undertaken to further elucidate the pathogenesis of preterm birth
by means of traditional risk factors and new markers for preterm birth derived from
the Preterm Prediction Study. Study Design: A total of 3076 women (2929 with singleton gestations and 147 with twin pregnancies)
were categorized according to the presence of risk factors including black race, low
body mass index, the presence of bacterial vaginosis, and previous preterm birth.
At 24 and 28 weeks’ gestation cervical length was measured and categorized as short
(≤25 mm) or normal (>25 mm). Vaginal and cervical fetal fibronectin concentrations
were measured at 24, 26, 28, and 30 weeks’ gestation and results were categorized
as positive (≥50 ng/mL) or negative (<50 ng/mL). Results: At 24 to 26 weeks’ gestation women with each of the risk factors were more likely
to have positive fibronectin test results or to have a short cervix. Among women with
negative fetal fibronectin results at 24 to 26 weeks’ gestation those with a short
cervix were more likely to have positive fetal fibronectin results at 28 to 30 weeks’
gestation, and among those with normal cervical length those women who had positive
fetal fibronectin results were more likely to have a short cervix at later evaluation.
Most women who had positive fetal fibronectin results at 24 to 26 weeks’ gestation
had negative results at 28 to 30 weeks’ gestation, whereas most but not all women
who had a short cervix at 24 to 26 weeks’ gestation still had a short cervix at 28
to 30 weeks’ gestation. In each period women with both a positive fetal fibronectin
result and a short cervix were at substantially increased risk of spontaneous preterm
birth; women with either marker alone had intermediate and approximately equal risks
of spontaneous preterm birth, and women without either marker had a low risk of spontaneous
preterm birth. Conclusion: Regardless of other risk factors, a short cervix predicts a subsequent positive fetal
fibronectin result, and a positive fetal fibronectin result predicts subsequent cervical
shortening. These data do not support a single sequence of events leading to spontaneous
preterm birth. (Am J Obstet Gynecol 2000;182:636-43.)
Keywords
To read this article in full you will need to make a payment
Purchase one-time access:
Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online accessOne-time access price info
- For academic or personal research use, select 'Academic and Personal'
- For corporate R&D use, select 'Corporate R&D Professionals'
Subscribe:
Subscribe to American Journal of Obstetrics & GynecologyAlready a print subscriber? Claim online access
Already an online subscriber? Sign in
Register: Create an account
Institutional Access: Sign in to ScienceDirect
References
- The length of the cervix and the risk of spontaneous premature delivery. National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network.N Engl J Med. 1996; 334: 567-572
- The Preterm Prediction Study: fetal fibronectin testing and spontaneous preterm birth.Obstet Gynecol. 1996; 87: 643-648
- The Preterm Prediction Study: significance of vaginal infections. National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network.Am J Obstet Gynecol. 1995; 173: 1231-1235
- The Preterm Prediction Study: patterns of cervicovaginal fetal fibronectin as predictors of spontaneous preterm delivery. National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network.Am J Obstet Gynecol. 1997; 177: 8-12
- The Preterm Prediction Study: a clinical risk assessment system.Am J Obstet Gynecol. 1996; 174: 1885-1893
- The Preterm Prediction Study: maternal stress is associated with spontaneous preterm birth at less than thirty-five weeks’ gestation. National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network.Am J Obstet Gynecol. 1996; 175: 1286-1292
- The Preterm Prediction Study: risk factors in twin gestations. National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network.Am J Obstet Gynecol. 1996; 175: 1047-1053
- The Preterm Prediction Study: the value of new vs standard risk factors in predicting early and all spontaneous preterm births. NICHD MFMU Network.Am J Public Health. 1998; 88: 233-238
- The Preterm Prediction Study: recurrence risk of spontaneous preterm birth. National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network.Am J Obstet Gynecol. 1998; 178: 1035-1040
- The Preterm Prediction Study: fetal fibronectin, bacterial vaginosis, and peripartum infection. NICHD Maternal Fetal Medicine Units Network.Obstet Gynecol. 1996; 87: 656-660
- Fetal fibronectin in cervical and vaginal secretions as a predictor of preterm delivery.N Engl J Med. 1991; 325: 669-674
- Reliability of diagnosing bacterial vaginosis is improved by a standardized method of gram stain interpretation.J Clin Microbiol. 1991; 29: 297-301
Article Info
Publication History
Accepted:
November 2,
1999
Received in revised form:
September 15,
1999
Received:
April 16,
1999
Footnotes
*Supported by National Institute of Child Health and Human Development grants HD21410, HD21414, HD21434, HD27860, HD27861, HD27869, HD27883, HD27889, HD27905, HD27915, HD27917, and HD19897.
**Reprints not available from the authors.
Identification
Copyright
© 2000 Mosby, Inc. Published by Elsevier Inc. All rights reserved.
