Abstract:

Background: In developed countries, uterine scar thickness ≥2.5mm has been associated with successful vaginal birth after caesarian section, The use of ultrasound has practical application in measuring uterine scar thickness for pregnant women with previous caesarian delivery, The study aimed on identifying associated factors and predictors of uterine scar thickness for women with prior caesarian-section.

Objective: To determine uterine scar thickness, associated factors, and predictors among pregnant women with previous caesarian scars at Bugando Medical Centre.

Methodology: This was an analytical cross-sectional study where pregnant women consecutively enrolled in the study during antenatal clinic in the third trimester from 36 weeks. Uterine scar thickness was measured using ultrasound. Data was analyzed using STATA version 15. Chisquare (χ2) or Fisher exact test was applied to test for the significance of association, while logistic regression analysis was used to determine predictors with a p-value of < 0.05 considered statistically significant.

Results: A total of 400 pregnant women at Bugando Medical Centre with previous caesarian scars were enrolled, with a cut-off point of <2.5mm as a thin uterine scar. The majority (72%) of study participants had a thick uterine scar, while the minority (28%) had thin uterine scars. Interpregnancy interval (≥18 months), no history of wound infection, normal EFW, normal AFI, and an anterior placental location had a significant association with a thick uterine scar (p<0.001, p=0.006, p=0.002, p<0.001, and p=0.03, respectively). On multivariate logistic regression, a longer interpregnancy interval and normal AFI were found to be significant predictors of a thick uterine scar (AOR=2.3, 95%CI=0.10-0.60, p=0.001 and AOR=0.2, 95%CI=0.10-0.60, p=0.002 respectively).

Conclusion: Inter-pregnancy interval, amniotic fluid index, and gestational age were significantly associated with and predicted uterine scar thickness in women with previous cesarean deliveries.