Oral contraceptive use and cervical intraepithelial neoplasia.

ABSTRACT

PIP: Between September 1987 and November 1988, 103 University of North Carolina Hospitals (UNCH) Dysplasia Clinic patients with newly diagnosed, biopsy-confirmed cervical intraepithelial neoplasia (CIN) II or CIN III were enrolled as cases. They were 18-45 years old, black or white, nonpregnant North Carolina residents. 40 cases were CIN II and 63 cases were CIN III confirmed histologically. The controls were 258 UNCH Family Practice Center patients with normal cervical cytology. All subjects participated in a 15-minute structured interview. The Hollingshead Index was used as a proxy for socioeconomic status (SES). Known risk factors for cervical neoplasia were found to be risk factors for CIN II and CIN III. Compared with controls, cases were younger (odds ratio [OR] = 3.4 for those under 25 years of age), less educated (OR - 13.3 for 13 years), and of lower SES. Cases were more likely to have been divorced (OR - 2.7), to be cigarette smokers (OR = 3.4), to have ever been pregnant (OR - 2.6), to have had more than 2 sex partners (OR = 5.0), to have reported having had a sexually transmitted disease (gonorrhea, chlamydia, herpes, venereal warts, or pelvic inflammatory disease) (OR = 2.9), and to have had at least 3 Pap smears in the 5 years prior to study recruitment (OR = 1.7). Cases were less likely to have used a barrier method of contraception (OR = 0.3). 80.6% of cases and 81.0% of controls had ever used oral contraceptives (OCs); thus, the crude OR was 1.0. Adjustment of the OR for all confounders (age, SES, ever-use of barrier methods, smoking history, age at 1st sexual intercourse, lifetime number of male sex partners, current marital status, and number of Pap smears) reduced the OR to 0.7 (95% confidence interval 0.3-1.6). Recency, latency, duration, and age at 1st OC use were compared without finding any positive association between OC use and CIN.