Is asymptomatic bacteriuria associated with short cervical length in women with a singleton pregnancy, a secondary analysis of two national cohort studies with small embedded randomized controlled trials.

OBJECTIVE

To assess the association between asymptomatic bacteriuria (ASB) and short cervical length (CL), since they are both associated with preterm delivery.

STUDY

DESIGN

In two prospective multicentre cohort studies, pregnant women were screened for the presence of ASB and short CL (≤25 mm). We compared CL in women with and without ASB. Both studies had a small randomised clinical trial embedded.

RESULTS

Our study population comprised 1 610 women, of whom 114 were ASB positive. Median cervical length was similar in women with and without ASB (44.0 vs 44.0 mm, P = 0.60). More women in the ASB positive group had a short CL compared to the ASB negative group (1.8 % versus 0.4 %, P = 0.047)). The gestational age at delivery did not differ between the groups (ranging from 38 + 3 in women with ASB and short CL to 39 + 5 in women without ASB with a short CL P = 0.52). No preterm births occurred in women with a short cervical length (regardless of ASB status). In the women without ASB and no short CL 4.8 % had a preterm birth, in the women with ASB but not a short CL 4.1 % had a preterm birth.

CONCLUSION

While ASB status did not influence median cervical length, we found a significant relationship between a short CL and ASB positive women. We found no statistical significant difference on the preterm birth rate and mean gestational age.