Risk Factors of Genital Tract Lacerations at Yaoundé Central Hospital - Cameroon: A Case Control Study

Background: Genital tract lacerations are lesions resulting from breakage of continuity of the lower genital tract during birth. This includes precisely the cervix, vagina, vulva and perineum. Genital tract lacerations are common causes of maternal morbidity and mortality. A good knowledge of risk factors can prevent complications.

Aim: Our general objective was to determine the risk factors for genital tract lacerations.

Study Design: Case-control study.

Place and Duration of Study: Five months (from January 2015 to May 2015) at the Obstetrics and Gynecology Unit of Yaoundé Central Hospital.

Methodology: Once identified, women who had suffered genital tract lacerations were interviewed, after which they underwent physical examination aimed at identifying the laceration site and type. We paired these women to those of same age and parity who did not have genital tract laceration (control group). Data were collected using a questionnaire and analyzed with Epi info software version 3.5.1 with a significance level of P< 0.05.

Results: Out of 1250 deliveries, 150 women had genital tract laceration, giving the prevalence of 12%. But we excluded 14 and retained 136 women as cases. Perineal tears accounted for 92.6% of genital tract lacerations, cervical tears 8.8% and vaginal tears 7.4%. Maternal risk factors were: past history of perineal tear (OR=5.05; 95% CI :1.9-13.7; p=0.00), length of the perineum < 4 cm (OR=33.72; 95% CI:17.2-66.02; p=0.00), duration of expulsion < 30 minutes (OR=3.16; 95%CI:1.9-5.2; p=0.00) and duration of active phase of labor < 6 hours (OR=5.01; 95% CI:2.8-8.9; p=0.00). Iatrogenic risk factors were: induction of labor (OR=9.57; 95% CI: 2.1-42.1; p=0.00) and augmentation of labor (OR=3.79; 95%CI: 2.1-6.6; p=0.00). The only fetal risk factor was birth weight >4000 g (OR=7.32; 95% CI:1.8 - 60; p=0.03).

Conclusion: Prior to delivery and in order to prevent trauma to the genital tract, the following risk factors should be sought out for: past history of perineal tears, perineal lengths less than 4 cm, duration of the active phase of labour less than 6 hours, induction and augmentation of labor with newborn birthweights of more than 4000 g and expulsive phases lasting less than 30 minutes. Also, care providers are advised to perform episiotomies in women presenting these risk factors.