Cervical carcinogenesis and contraception

Cytologic evaluation of cervical smears has been carried out in 3,374 women who used different modes of contraception (Lippes loop, copper T200, copper T220, copper devices containing higher copper content than the copper T200, CuT380 Ag, levonorgestrel IUD, injections of noresthisterone oenanthate, and subdermal implants of levonorgestrel) under the Contraceptive Testing Programme of Indian Council of Medical Research for periods ranging from 6 months to 15 yr. While no case of severe dysplasia or malignancy was noticed with any type of contraceptive, 113 dysplastic smears (99 mild and 14 moderate) were encountered on follow-up, giving an incidence of 3.3%, which was statistically insignificant compared with the pretreatment incidence of 1.4% (47 of 3,374). The highest incidence of dysplasia was seen with devices containing a high copper content (9.2%), followed by CuT200 (6.1%) and levonorgestrel implants (4.2%), and was lowest with Lippes loop (1.8%), injection of noresthisterone oenanthate (1.7%), and CuT380 Ag (1.5%), but statistics higher than the pretreatment incidence of 1.4% were seen only with CuT200 and devices containing high copper content. Retrogression of dysplasia was seen in 85 of the 94 posttreatment dysplasia cases and in all 47 pretreatment dysplasia cases, whereas in the remaining nine posttreatment cases of dysplasia the lesion persisted for 6-12 mo, necessitating discontinuation of contraception. The accumulated follow-up data indicate that the CuT380 Ag device is a promising IUD for the future in view of its low incidence of dysplasia determined during its use up to 5 yr. However, more prolonged follow-up in larger numbers of subjects is required to confirm its innocuousness on long-term retention.