Objective: To review our practice of diagnosing and managing third and fourth degree perineal tears.
Method: Retrospective case series conducted by reviewing medical records of all women having singleton, full term vaginal delivery at Aga Khan University Hospital, Karachi from November 1990 to October 2005.
Results: The frequency of obstetric anal sphincter injury (OASI) in our department was 0.5% (135) out of a total of 26,844 vaginal deliveries. Seventy five percent were nulliparous (102). Forceps delivery was performed in 86 patients out of 135 (63.7%). In only 28 patients (20.7%), the diagnostic criterion for classification of third degree tears was used. For the repair of third degree tear end-to-end method was performed on 97 (71.9%) patients. Twenty nine women had subsequent uncomplicated vaginal deliveries. None of these patients were subjected to endo-anal ultrasonography and/or anal manometry. The documented evidence regarding planning of future delivery was found in only 4 cases.
Conclusion: The frequency of distribution of third and fourth degree perineal tear in our study was 0.5% which is significantly lower than clinically suspected or recognized. Our study shows that 75.5% patients were nulliparous and the use of forceps for delivery was 63.7% among more than 50% of these patients. This indicates that forceps delivery if possible should be avoided or substituted with vacuum delivery which has a lower incidence of OASI. Most of the management was according to international accepted standards except that 72.3% were stitched under local analgesia