Failed sterilisation: evidence-based review and medico-legal ramifications.

Sterilisation is one of the most common procedures in the world. Around 50,000 female sterilisations are performed every year in the UK, although there is a suggestion of a worldwide downward trend in sterilisation procedures. Surgical techniques used in female sterilisation are designed to prevent pregnancy by occluding tubal patency through mechanical device application, electrocautery or by tubal excision and separation. These are shown in Table 1. Laparoscopic tubal occlusion by clip or ring is the preferred method of female sterilisation in the UK, and has replaced the earlier preference for tubal electrocautery. Laparoscopic sterilisation using the Filshie clip is the principal method in Europe, Canada and Australia and is becoming popular in the USA since licensing in 1996. Conception occurring after sterilisation is termed failed sterilisation, and can occur several years after the procedure; one case was described after an interval of 23 years. Complications can occur during sterilisation. The complication rate of interval laparoscopic sterilisation in one large multicentre study was 4.5 per 1000, with vascular or bowel injury, or inability to complete sterilisation laparoscopically, cited as the main reasons for conversion to laparotomy. Other complications include intractable localised pelvic pain, mesosalpingeal tears, tubal transection, tubal torsion and necrosis, tubo-ovarian abscess, uterine perforation, thermal bowel injury by electrocoagulation, pelvic or wound infection, delayed migration of Filshie clips (urethra, rectum, vagina), psychological symptoms and regret. Mortality attributed to the sterilisation procedure is extremely low, and has been estimated to vary from 1 to 2 per 100,000 for procedures performed in the United States, to 4 per 100,000 in developing countries, and is consequent to operative and anaesthetic related complications. Of significance, sterilisation decreases the risk of ovarian cancer but increases the risk of subsequent hysterectomy and ectopic pregnancy.