Effectiveness of female voluntary surgical contraception

154000 women in Brazil were assisted in family planning from 1978 to 1989 by CPAIMC (Research Center for Integrated Assistance to Women and Children) and 24800 of these women underwent sterilization. Most of the complications which occurred in 5% of the cases were lesions or were related to visualization of the internal genital organs. The number of live births per woman declined from 6.2 in 1960 to 5.6 in 1970 4.5 in 1980 and probably 3.4 in 1990. The most frequently used contraceptive method is tubal ligation; the next is oral contraceptives. It is estimated that 27% of married women aged 15-44 have been sterilized. In order to study the failure rate of tubal ligation CPAIMC collaborated with the US Centers for Disease Control to analyze the data of 13423 female sterilizations carried out from 1981-84. 97% of the interventions were performed by laparoscopy after occlusion was carried out by Yoon rings. 24% of the procedures occurred during the training of surgeons in sterilization techniques. Each doctor performed 1-15 procedures per day. Accumulated failure rates were determined after 6 12 24 36 and 48 months. 144 women became pregnant after sterilization 22 of which were excluded because it was determined that they had been in the luteal phase (the cycle began 2 weeks prior to the operation). The failure rate increased from .54% after 12 months to .99% after 35 months and stayed even thereafter (1% after 48 months) which was comparable to international standards. After 12 and 24 months the rate was significantly lower for the oldest women as compared to the youngest ones. Parity was not a factor nor did the type of procedure matter; only an increased number of surgeries per day affected the rate slightly. The improvement of surgical techniques from 1981-84 reduced the failure rate. 5.7% of failures ended in ectopic pregnancy (mostly among those aged 30-34 who had delivered 3 or 4 children) which was low compared to the 15.7% rate of a Singapore study. A third of the women who became pregnant returned for a second operation. The long-term risk of tubal ligation have to be communicated to clients as well as the risk of failure after the first year.