EP17.16: Screening for low‐tract genital infections in asymptomatic women at increased risk for preterm birth

To evaluate the association between low-tract genital infections and preterm birth in asymptomatic women at increased risk for preterm birth (PTB). Retrospective single-centre cohort study performed in a referral hospital from January 2019 to December 2021. Asymptomatic women at increased risk for PTB because of cervical shortening <25mm before 24 weeks gestation or anamnestic factors were followed up in an outpatient clinic at Brescia University Hospital. Multiple pregnancies were excluded. Vaginal swabs were performed at presentation. The incidence of PTB was compared according to microbiological test at presentation. The Chi-squared test and Fisher‘s exact test were used for the analysis of contingency tables of proportions in different groups, as appropriate, p value <0.05 was considered statistically significant. Vaginal swabs were performed in 190/205 (92.7%) patients. Childbirth data were not available for 31/190 patients (16.3%). PTB occurred in 5/159 cases <28 weeks (3.14%), in 13/159 cases <34 weeks (8.2%) and in 29/159 <37 weeks (18.2%). Low-tract genital infections were found in 116/190 cases (61%). In 13/116 cases childbirth data were not available. PTB occurred in 3/103 <28 weeks (2.9%), in 11/103 <34 weeks (11.7%), in 21/103 <37 weeks (20.4%). Vaginal swabs resulted negative in 74/190 cases (38.9%). Gestational age at delivery was not known in 18/74 case (24.3%). In this group PTB <28 weeks was found in 2/56 (3.6%), <34 weeks in 2/56 (3.6%) and <37 weeks in 8/56 (14.2%). The incidence of PTB <28 (p = 1), <34 (p = 0.137) and <37 weeks (p = 0.341) was not significantly different between women with positive or negative vaginal swab at presentation. Low-tract genital Infections are not associated to PTB in asymptomatic women at increased risk for preterm birth.