We wanted to compare the two methods through a RCT with the end-points examination results after one year addressing endoanal sonography findings, anal manometric results and continence score evaluated by a Weksner score questionnaire. Our study is performed in the routine clinical setting. The patients are recruited to the study during delivery when the injury is recognized. When she has given her informed consent she is randomized to one of the two operation methods. The operation is performed by the consultant obstetrician on call or the resident supervised by the consultant. The proctologist who performs the anal manometry and sonography after one year is blinded to the surgical method.