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Vaginal exposures to talc and other particulates may play an etiologic role in epithelial ovarian cancer. Surgical sterilization may protect against ovarian cancer by blocking entry of such particulates into the peritoneal cavity. The authors assessed histories of talcum powder use, tubal sterilization, and hysterectomy with ovarian conservation in 188 women in the San Francisco Bay Area with epithelial ovarian cancers diagnosed in 1983-1985 and in 539 control women. To investigate the roles of blood-borne environmental exposures on ovarian cancer risk, they assessed lifetime consumption of coffee, tobacco, and alcohol in these women. Of the 539 controls, 280 were hospitalized women without overt cancer, and 259 were chosen from the general population by random digit telephone dialing. Ninety-seven (52%) of the cancer patients habitually used talcum powder on the perineum, compared with 247 (46%) of the controls. Adjusted for parity, the relative risk (RR) = 1.40, p = 0.06. There were no statistically significant trends with increasing frequency or duration of talc use, and patients did not differ from controls in use of talc on sanitary pads and/or contraceptive diaphragms. Fewer ovarian cancer patients (7%) than controls (13%) reported prior fallopian tube ligation (RR, adjusted for parity, = 0.56, p = 0.06), and fewer patients (20%) than controls (28%) reported prior hysterectomy (RR = 0.66, p = 0.05). The protective effect of hysterectomy was confined to those who underwent this surgery 10 or more years prior to interview and to those who had not undergone prior tubal sterilization. Consumption of cigarettes and alcohol did not differ between cases and controls. By contrast, 11 (6%) cases never regularly consumed coffee, compared with 31 (11%) hospital controls and 26 (10%) population controls (RR, adjusted for smoking, = 2.2, p = 0.03, for the comparison using all controls). Overall, ovarian cancer risk among women who had drunk coffee for more than 40 years was 3.4 times that of women who had never regularly consumed coffee (p less than 0.01). However, the data exhibited no clear trends in risk with increasing consumption. Although risk ratios relating duration of coffee drinking to ovarian cancer were unaffected by adjustment for several characteristics, further study is needed to exclude potential confounding by other unmeasured characteristics.

In two case-control studies conducted in the six-county San Francisco Bay Area, 111 women diagnosed with epithelial ovarian carcinoma in 1974-1977 and 188 women diagnosed in 1983-1985 were interviewed concerning their menstrual, sexual, and reproductive histories. For comparison, interviews were conducted with 752 control women admitted to the same hospitals within six months of the cases; for cases diagnosed in the later period, interviews were also conducted with an additional 259 population-based controls selected by random digit dialing. Controls were matched to cases by age and race. Qualitative and quantitative findings were similar for the two studies. In the combined data, cases were more likely than their matched controls to have been nulliparous, to have undergone menarche at an early age, and to have refrained from using oral contraceptives. Menopause occurred slightly later for cases than for controls, but the differences were not statistically significant. Neither age at first term pregnancy (20 or more weeks gestation) nor number of term pregnancies was predictive of ovarian cancer risk. The protection afforded by oral contraceptive use was independent of parity, and it increased with increasing duration of use. There were no trends in risk with time since last oral contraceptive use or with time since first use, after adjustment for duration of use. These observations suggest that oral contraceptive use decreases risk for ovarian cancer, rather than merely indicates fertility, which may itself decrease risk of developing the disease. The authors combined reproductive characteristics and oral contraceptive use to estimate a woman's total duration of ovulation, which was positively associated with ovarian cancer risk (p less than 0.001 for trend). These observations support the concept that the greater the duration of ovulation or accompanying endocrinologic phenomena, the greater a woman's risk for ovarian cancer.

Relationships between ovarian cancer and ability to conceive were explored in a case-control study of 188 women with histologically confirmed epithelial ovarian cancer and 539 control women in the San Francisco Bay Area. Control women consisted of two groups: those hospitalized without cancer, matched to cases by age, race, and hospital of diagnosis (n = 280); and those selected from the general population by random digital dialing, matched to cases by age, race, and telephone prefix (n = 259). Ovarian cancer risk among nulliparous (but not parous) women was positively associated with a history of unsuccessful attempts to conceive, of physician-diagnosed infertility, and of doubts about ability to conceive. Among all women, risk increased with increasing years of unprotected intercourse (P value for trend = 0.02). Risk among women having 10 or more yr of unprotected intercourse was 1.8 relative to that among women having less than 2 such yr (P = 0.01). This association was independent of parity, oral contraceptive use, and estimated years of ovulation, each associated with ovarian cancer. Further, duration of unprotected intercourse combined multiplicatively with each of these latter characteristics in increasing ovarian cancer risk. For example, while cancer risk exhibited a 2-fold range from lowest to highest years of unprotected intercourse and a 4-fold range from lowest to highest years of ovulation, risk among women in the highest joint category of these characteristics was 8 times that of women in the lowest category. We believe that some abnormality of ovulation that reduces the likelihood of conception plays a role in epithelial ovarian cancer.

A pilot study was conducted to determine whether any relationship exists between mutagenicity of a women's uterine cervical mucus and her current smoking status. Cervical fluids obtained from 78 premenopausal women seen between July 1983 and March 1984 at the University of California, San Francisco Dysplasia (and diethylstilbestrol) Clinic or in a private practice were tested for mutagenicity by means of the Ames-Salmonella microsomal test. Of 36 current smokers, 14 (39%) had positive tests as compared to 5 of 42 nonsmokers (12%). The odds ratio (OR) estimate was 4.7 with 95% confidence limits (CL) of 1.6-14.2. Secretions from 14 of 32 (44%) women who had smoked during the day of the sample collection--within the previous 7 hours--were positive on the laboratory test, whereas none of the 4 women was positive who had smoked 8 hours or more before the specimens were obtained. Fluids from women with dysplasia or carcinoma in situ were more likely to be mutagenic than were those from other women, although this finding may be due to chance (OR = 2.0 with 95% CL of .70-5.9). This relationship between smoking and mutagenic cervical fluids offers evidence that might help to explain the association between cervical cancer and cigarette smoking noted in previous epidemiologic studies.