[Is the bacterial vaginosis risk factor of prematurity? Study of a cohort of 1336 patients in the hospital of Arras]

Background: Among risk factors of prematurity, bacterial vaginosis (BV) could play an important role, but few studies took place in our country.

Aim: In a French population of women booking in a hospital maternity, to search a link between prematurity and BV in the first trimester of pregnancy.

Methods: A hospital cohort study was carried out between May 2006 and September 1(st), 2009. Pregnant women were screening for BV before 13+6 weeks' gestation. BV was determined by a Gram-Stained Vaginal score greater or equal to 7.

Results: One thousand three hundred and thirty-six patients were included in the study among whom 203 patients had BV and 1133 patients did not have. The presence of BV was significantly associated with preterm delivery (OR: 1.6; 95% IC: 1.1-2.7). But this increase concerned only the spontaneous prematurity (ORa: 1.8, 95% IC: 1.0-3.2) and the statistical association disappeared after taking into account maternal tobacco addiction and socio-economic weak level (ORa: 1.6; 95% IC: 0.9-2.9). At the patient with BV, moreover, the risk of miscarriage before 16SA was significantly augmented at the patient with BV (OR: 3.4; 95% IC: 1.1-10.4), but this risk disappeared after taking into account tobacco addiction and maternal level of studies (ORa: 1.9; 95% IC: 0.5-7.2).

Conclusion: The presence of BV in the first trimester of pregnancy seems to be associated with increased risks of preterm delivery and early spontaneous miscarriage. However, this relation seems to be partly linked to a level of weaker study and a more frequent tobacco addiction among the women with BV.