Short and inflamed cervix predicts spontaneous preterm birth (COLIBRI study)

Abstract

Objective: To develop a new strategy of predicting spontaneous preterm birth (sPTB) by combination of transvaginal ultrasound (TVUS) assessment and inflammatory proteins detection in vaginal secretions.

Methods: Prospective study of 87 women referred for cervical length assessment with a standardized TVUS combined to vaginal secretions sampling. Samples were analyzed for presence of 10 cytokines. Main outcome was sPTB (<37 weeks of gestation). Associations were assessed with the chi-square, Fisher’s exact test (p < 0.05) and Wald’s logistic regression.

Results: sPTB occurred in 25.3% of women at a median gestational age of 35.6 weeks of gestation. Short cervix (<25 mm) (n = 24) was associated with sPTB (p < 0.01) as interleukine (IL)-1β, IL-8 and IL-10 in vaginal secretions (p < 0.05). In multivariate analysis, short cervix and IL-8 in vaginal secretions were independently associated with sPTB (OR 3.58 (95%CI 1.02; 12.61) and 14.55 (95%CI 1.64; 128.83), respectively) as their combination (OR 4.33 (95%CI 1.25; 14.95)). By categorizing cervical length by presence of IL-8, sPTB occurred in 55.6% of women with a short inflamed cervix.

Conclusion: COLIBRI study used a novel, single-step method of vaginal secretions sampling during TVUS and demonstrated that combination of short cervix and IL-8 in vaginal secretions is a promising sPTB predictive test.

• Cervical length
• cytokines
• inflammation
• pre-term birth
• transvaginal ultrasound
• vaginal secretions

Acknowledgements

The authors wish to thank Dr Louise Constantineau and Mrs Josée Poulin for their expertise and help to develop the standardized TVUS method. They are thankful to Dr Daniel Blouin, Mrs Lise Lavoie, Mrs Amélie Léveillé, Mrs Marie-Pier Labbé and the ultrasound technologists at the MFM-clinic of the CHUS for their technical support. They are grateful to Mrs Tania Fayad for her precious help in the writing process and to all patients who agreed to participate in the study.

Notes

*Results were presented at: SMFM 30th Annual Meeting – The Pregnancy Meeting^tM, Chicago, IL, February 1–6, 2010; SMFM 31st Annual Meeting – The Pregnancy Meeting^tM, San Francisco, CA, February 7–12, 2011.