Cervical length measured by transvaginal ultrasonography and cervicovaginal infection as predictor of preterm birth risk.

Abstract

Introduction:The study shows possibilities of transvaginal sonographic measurement of the cervix in prediction of premature birth risk.Goals:The aim of the study was to follow up the cervical length in the pregnant from 16th to 37th week, as well as to do a microbiological analysis of the vaginal and cervical flora and to identify relation between the cervical shortening and microbiological flora as well as with a premature birth.Material and methods:The investigation was conducted as a prospective study on two groups of female patients in Clinical Centre of Banja Luka. In the high risk group we had 8% of patients with cervical length bellow than 15mm, 30% of patients with cervical length from 15 to 25m and 62% of patients with cervical length bigger than 25mm. In the low risk group we had no patients with cervical length bellow 15mm, 95% of patients had cervical length bigger than 25mm and 5% of patients had cervical length from 15 do 25mm.Results:The regression coefficient of the cervical length in the high risk group was 0.44mm, while in the low risk group it was 0.26mm. In the high risk group 67.56% patients had a positive cervical smear finding, while in the low risk group it was 4%. A high premature birth (defined as birth before 36.6 weeks) incidence of 50% was presented in patients with cervical length bellow 15mm. In the group of patients with cervical length up to 25mm the premature risk incidence was 10.52±0.05. In the high risk group of patients with a positive cervical smear finding, regarding the cervical length the percentage was as follows; in the subgroup of 15mm length 88,89±11,87, in subgroup from 15 to 25mm was 62,07±11,43 and in the subgroup bigger than 25mm, 60.06±8.05.Conclusion:By the analysis of the first and second goal of our study we can conclude that ultrasound assessment of cervical length is simple and feasible in the 16th week of pregnancy in both groups, with high and low risk. The length of the cervix in this period is shorter in the high risk group compared with the low-risk group. This difference was not statistically significant, however, it clearly demonstrated connection between shorten length of the cervix with the preterm birth. A regression analysis shows that the shortening of the cervix length is more frequent in high risk group which is to be expected, bearing in mind that in this group, the risk of preterm delivery was significantly higher.