Cervical cytology associated with levonorgestrel contraception

Cytologic monitoring of cervical smears was carried out in 686 women receiving two modes of levonorgestrel contraception, one in the form of a subdermal implant and the other as an intrauterine device. The period of contraception with both delivery systems ranged from six months to five years. No case of malignant neoplasia was seen in any of the 44 subjects even after five years of continued levonorgestrel contraception. Preinsertion cytology revealed eight dysplastic smears (seven mild and one moderate); the lesions reverted to normal six months later and remained normal after one to four years of hormone use. A total of 19 dysplastic smears (18 mild and 1 moderate) were detected in the postinsertion smears collected after one to five years of contraception, giving an incidence of 2.8%, which was nonsignificant when compared with the control figure of 1.3%. Regression of the lesion to normal was observed in all 19 dysplasias on follow-up and in none did the dysplasia progress to a higher grade or frank malignancy. The incidence of dysplasia was more than twice as high with the intrauterine device as with the implant (4.9% vs. 2.1%). Hence, the implant appeared to be safe during five years of contraceptive use in terms of cervical pathology. However, longer follow-up of a large number of women is needed to reach a definitive conclusion.