A Case-Control Study of Obstetric Fistula Risk Factors in the Democratic Republic of the Congo

Abstract

Background: Pregnant women in the Democratic Republic of Congo (DRC) are at increased risk for developing obstetric fistulas (OFs) as a result of obstructed labor, in conditions similar to many other African countries. No case-control study of biological and social risk factors for OF has been reported from the DRC. This study aimed to identify factors that would aid in prevention and early identification of women who are at risk of developing OF. Methods: Participants were enrolled in a case-control study at four obstetric clinics in the central DRC. Cases of OF were evaluated as they presented, then a control participant was enrolled among women presenting subsequently to the same clinic, seeking to match parity at the time of the fistula and tribe of the case. A questionnaire was administered to elicit physical, obstetric, demographic, socioeconomic, religion, geographic, and delivery attributes of the participants. Case-control comparisons sought to identify independent risk factors for OF in the total case-control pairs and in subgroups of the participants. Logistic regression was utilized to identify independent risk factors for OF in the total case-control study group and in selected subgroups of the participants, and linear regression was utilized to estimate the variation explained between case and control outcomes from the variables independently significant in the logistic regression models. Results: A total of 177 case-control pairs were enrolled. Among all pairs, shorter height of the case (odds ratio = 1.06, 95% Confidence Limits 1.02 - 1.12); more kilometers travelled to the delivery site (1.02, 1.01 - 1.02); her village, not town, residence (OR = 5.52, 2.72 - 11.2), and her lower professional status (2.95, 1.53 - 5.72) were statistically independent factors associated with OF development. When applied in linear regression comparison of the pairs, these variables yielded an r2 = 0.48, imputing 48% of the difference in delivery outcome between the pairs was explained by these variables. Among the 38 pairs who were primigravida, the independent variables were more kilometers travelled to the delivery site (1.02, 1.00 - 1.05), village, not town, residence (50.0, 10.2 - 248.7), and facility intended for lower patient acuity (3.7 s, 1.01 - 13.6, r2 = 0.66) patients who were matched on parity and tribe, the significant risk factors were professional status (OR = 0.29), greater distance travelled to the clinic (OR = 1.02, 1.01 - 1.02), village, not town, residence (5.52, 2.72 - 11.2), and mother’s lower professional status (2.95, 1.53 - 5.72) when the OF occurred. Conclusions: Our study showed biological and social factors associated with the development of OF. Shorter height was the only biological risk factor found to be statistically significant in the study population. Other factors were related to limited resources and limited access to medical care.