Prevalence and clustering of menopausal symptoms in older women by hysterectomy and oophorectomy status

This study examines the association of hysterectomy and oophorectomy with the prevalence and clustering of menopausal symptoms in a large population-based sample of older women. Subjects were 1121 women aged 50-89 from the Rancho Bernardo Study. Information on menopause, hysterectomy, oophorectomy, estrogen use, and other covariates was obtained in 1984-1987. A 1989 mailed survey obtained information on menopausal symptoms. In this sample, 22.1% reported hysterectomy with bilateral oophorectomy, and 25.3% reported hysterectomy with ovarian conservation. Mean time since hysterectomy was 26 (+/-12) years. Overall, 37% reported current estrogen use, and 40% reported past use. The duration of estrogen use was longer for women who had a hysterectomy (p < 0.001). Age-adjusted comparisons indicated that more women who had a hysterectomy, with or without bilateral oophorectomy, reported greater energy after menopause (p = 0.003 and p = 0.001, respectively), and more women with bilateral oophorectomy reported greater interest in sex (p = 0.007) and that life was getting better (p = 0.012) than women with natural menopause. Principal components factor analysis of the symptom data for all women yielded four factors: psychological, vasomotor, positive feelings, and self-image. Analyses performed within each group of women yielded similar factors and loadings. Adjusted comparisons of factor scores indicated that positive feelings were significantly higher in women who had a hysterectomy, with or without bilateral oophorectomy (p < 0.01) than in women with natural menopause. This difference was limited to current estrogen users. Vasomotor symptoms, psychological symptoms, and negative self-image did not differ by hysterectomy or oophorectomy status before or after stratification for estrogen use (p > 0.10). This study found after a hysterectomy, women are more likely to recall positive feelings about their menopause than women with natural menopause. Relief from symptoms leading to hysterectomy and use of replacement estrogen may be partly responsible. Results do not support the thesis that surgical menopause is associated with a sustained increased prevalence of vasomotor, psychological, or other symptoms.     

Hysterectomy status,estrogen use and quality of life in older women: The Rancho Bernardo study

OBJECTIVE: To examine the long-term effects of hysterectomy and use of estrogen replacement therapy on health related quality of life and symptom subscales in community dwelling postmenopausal women. METHODS: Information on menopausal history including hysterectomy and oophorectomy status, and history of estrogen use was obtained from a sample of 801 women aged 50-96 years at a clinic visit between 1992 and 1996. Within 1 week of the clinic visit, a standardized, validated quality of well-being (QWB) scale was administered over the telephone by a trained interviewer. RESULTS: Among these women, 25.2% reported hysterectomy with bilateral oophorectomy an average of 28 years earlier, and 11.0% reported hysterectomy with ovarian conservation an average of 26.5 years earlier. Age-adjusted comparisons indicated that women with natural menopause had slightly higher total QWB scores and lower symptom subscale scores than women in either of the hysterectomy groups (p's = 0.06). However, after additional adjustment for estrogen use and other potentially confounding covariates, there was no significant difference in total QWB score or on any subscale scores by hysterectomy and oophorectomy status. After adjustment for age, women who never used estrogen had significantly higher total QWB scores (p = 0.03) and significantly lower symptom subscale scores, indicating fewer symptoms, than those who were past or current users (p = 0.01). These differences persisted after adjustment for age, type of menopause, and behavioral and lifestyle covariates (p's = 0.008). CONCLUSIONS: There are no long-term adverse effects of hysterectomy or bilateral oophorectomy on health related quality of life. Lower total QWB and greater symptom subscale scores by women currently using estrogen may reflect an adverse effect of hormone use on health related quality of life in older postmenopausal women.     

The epidemiology of ovarian cancer: a population-based study in Olmsted County, Minnesota, 1935-1991

PURPOSE: To determine trends in incidence and survival between 1935 and 1991 and to evaluate risk factors for ovarian cancer among Olmsted County, Minnesota women. METHODS: All newly diagnosed cases of ovarian cancer among Olmsted County women in 1975-1991 were identified using the medical records linkage system of the Rochester Epidemiology Project. In order to assess trends, incidence rates in the subset of Rochester women were compared with Rochester rates for 1935-1974. Survival was evaluated by the Kaplan-Meier product-limit method. A case-control analysis of risk factors compared Olmsted County women with invasive epithelial ovarian cancer and an age-matched group of women from the community by logistic regression. RESULTS: Altogether, 129 Olmsted County women were newly diagnosed with ovarian cancer in 1975-1991. The age-adjusted (to 1970 United States whites) incidence rate was 22.5 per 100,000 person-years. Median survival from initial diagnosis was 3.7 years. Compared to an equal number of controls, the 103 women with invasive epithelial disease were more likely to be nulliparous (odds ratio [OR] 1.9; 95% CI 0.95-3.9) but less likely to have a history of thyroid disease (OR 0.4; 95% CI 0.2-0.8), hypertension (OR 0.4; 95% CI 0.1-0.9) or nonsteroidal estrogen use (OR 0.5; 95% CI 0.2-0.9). Prior hysterectomy (OR 0.5; 95% CI 0.2-0.9) and unilateral oophorectomy (OR 0.2; 95% CI 0.04-0.7) were also associated with reduced risk. CONCLUSION: The incidence of ovarian cancer in this community in 1975-1991 was little changed from rates 20 years earlier. There has been some improvement in survival from ovarian cancer in this population compared to 1935-1974, but still less than 50% survive for 5 years. Prior hysterectomy and unilateral oophorectomy appear protective for ovarian cancer.     

Deciding about Prophylactic Oophorectomy: What Is Important to Women at Increased Risk of Ovarian Cancer?

BACKGROUND: Little is known about the factors that women at increased risk of ovarian cancer consider to be important when deciding about prophylactic oophorectomy, surgery to remove the ovaries before they develop cancer. METHODS: Women who had undergone prophylactic oophorectomy (surgical group; n = 30) were compared with women who remained on the ovarian screening program (nonsurgical group; n = 28) on their importance ratings for a number of relevant decision-making factors. RESULTS: The most important decision-making factor across all subjects was reducing risk of ovarian cancer, but the single best predictor of group membership was the importance attributed to reducing cancer worry. Women who rated this factor as more important were more likely to be in the surgical group. No women identified the increased risk of heart disease and osteoporosis as issues for consideration. CONCLUSIONS: The desire to reduce cancer worry is likely to be the most important factor in a woman's decision to proceed to prophylactic oophorectomy. In view of the current imprecision in risk estimates given to women considering this option, cancer worry may override a more rational consideration of the costs and benefits of surgery.     

子宫肌瘤术中卵巢去留和对内分泌的影响

对于围绝经或绝经后妇女而言,因子宫肌瘤进行子宫切除的妇女,术中同时行预防性卵巢切除避免卵巢肿瘤的发生。但是,作为女性内分泌器官的卵巢,即使功能降低或停止,在手术切除后仍会引起妇女急性卵巢功能衰竭而出现相关症状,对妇女以后的生活产生不良影响。因此,子宫肌瘤行子宫切除时是否预防性切除卵巢一直存在争议。     

Hysterectomy, tubal sterilization, and the risk of breast cancer

Studies suggest that hysterectomy and tubal sterilization may alter the function of the remaining ovaries. Conceivably, this effect could alter breast cancer risk. To investigate whether these surgeries affect breast cancer risk, the authors analyzed data collected between December 1, 1980, and April 30, 1983, in a population-based, case-control study of women aged 20-54 years, the Cancer and Steroid Hormone Study. Compared with never-sterilized women, women with hysterectomy and no remaining ovaries had a decreased risk of breast cancer (relative risk (RR) = 0.7, 95% confidence interval (CI) = 0.6-0.8). Risk was lowest in women who had their surgery before age 40 years or 15 or more years in the past; surgery at an early age provided greater protection than surgery in the distant past. Hysterectomy with one or two remaining ovaries was also inversely associated with breast cancer risk (RR = 0.8, 95% CI = 0.7-0.9), but no relation was found with age at surgery or time since surgery. Women with tubal sterilization had a slightly increased risk of breast cancer, which was of borderline statistical significance (RR = 1.2, 95% CI = 1.0-1.3). However, no relation was found with age at surgery or time since surgery. The data suggest that hysterectomy with bilateral oophorectomy decreases the breast cancer risk in women aged less than 55 years, possibly by curtailing ovarian function at a critical period. However, neither hysterectomy without bilateral oophorectomy nor tubal sterilization appears to substantially alter breast cancer risk in women of this age.     

Breast cancer risk and ovariectomy, hysterectomy, and tubal sterilization in the women's contraceptive and reproductive experiences study

Removal or impairment of ovaries before menopause may affect a woman's breast cancer risk by altering her cumulative exposure to ovarian hormones. The Women's Contraceptive and Reproductive Experiences Study, a population-based, multicenter case-control study of incident invasive breast cancer, recruited women aged 35-64 years (4,490 cases and 4,611 controls) who provided data on ovariectomy, hysterectomy, and tubal sterilization during in-person interviews. Controls were frequency-matched to cases by age, race, and study site. Unconditional logistic regression analysis was used. Women who had not undergone premenopausal reproductive surgery were the referent group. Bilateral ovariectomy was associated with reduced breast cancer risk overall (odds ratio (OR) = 0.59, 95% confidence interval (CI): 0.50, 0.69) and among women <45 years of age (ORs ranged from 0.31 to 0.52), but not among those who were older at surgery. It was also associated with a reduced risk for estrogen and progesterone receptor-positive tumors (OR = 0.63, 95% CI: 0.52, 0.75) but not receptor-negative tumors. Hysterectomy with ovarian conservation (OR = 0.83, 95% CI: 0.72, 0.96) and hysterectomy with partial ovary removal (OR = 0.73, 95% CI: 0.59, 0.91) were also associated with lower risk. No association with breast cancer risk was observed with tubal sterilization only or partial ovariectomy without hysterectomy. Reproductive organ surgeries may alter ovarian hormone levels, thereby affecting breast cancer risk.     

Carotid wall thickness and years since bilateral oophorectomy: the Los Angeles Atherosclerosis Study

Evidence that coronary heart disease risk increases with surgical menopause is consistent. However, findings concerning atherosclerosis and surgical menopause are inconsistent. The Los Angeles Atherosclerosis Study (1995-1996) assessed the cross-sectional relation at baseline between years since bilateral oophorectomy and common carotid artery intima-media thickness (IMT). Participants included 269 employed California women asymptomatic for cardiovascular disease and aged 45-60 years. Ninety-seven women reported a hysterectomy: 42 without oophorectomy or a unilateral oophorectomy and 55 with a concurrent bilateral oophorectomy. IMT was measured bilaterally with B-mode ultrasound and was regressed on age, height, and years since hysterectomy in each group. Among women who had undergone bilateral oophorectomy, IMT was significantly related to years since hysterectomy (beta = 0.042 (standard error, 0.018) mm/10 years, p = 0.02). However, IMT was unrelated to years since hysterectomy in the no bilateral oophorectomy group (beta = 0.005 (standard error, 0.023) mm/10 years, p = 0.82). Adjustment for high density lipoprotein or low density lipoprotein cholesterol attenuated the association between IMT and years since hysterectomy by about a fourth in the bilateral oophorectomy group. Since over 90% of this group had a history of hormone replacement therapy use, the finding that years since bilateral oophorectomy was associated with increasing atherosclerosis conflicts with a well-known finding that such therapy reverses the adverse effect of bilateral oophorectomy on coronary heart disease.     

Tubal sterilization, hysterectomy, and the subsequent occurrence of epithelial ovarian cancer

Several hypotheses predict that tubal sterilization and hysterectomy may influence a woman's risk of developing ovarian cancer. To examine the relation between these surgeries and epithelial ovarian cancer, the authors analyzed data from the Cancer and Steroid Hormone Study, a case-control study of women aged 20-54 years. Eight population-based cancer registries in the United States identified women with newly diagnosed epithelial ovarian cancer during 1980-1982 (n = 494). A comparison sample of female residents of these eight areas (n = 4,238) was identified through random digit dialing. Women who had had tubal sterilization (relative risk (RR) = 0.69, 95% confidence interval (Cl) 0.50-0.95), a hysterectomy only (RR = 0.55, 95% Cl 0.38-0.81), or a hysterectomy with unilateral oophorectomy (RR = 0.60, 95% Cl 0.31-1.17) had lower risks of ovarian cancer than did women who had never had any sterilization surgery. However, the negative associations with tubal sterilization and hysterectomy only appeared to wane after two decades. These findings may be partly explained by the screening for occult ovarian pathology that often accompanies pelvic surgery: Women whose ovaries screen as "negative" may be temporarily at low risk of being diagnosed with ovarian cancer. However, because the decreased risks persisted for so long, it is conceivable that hormonal, mechanical, or circulatory sequelae of these sterilization procedures may act to lower ovarian cancer risk.     

Risk of myocardial infarction after oophorectomy and hysterectomy

To determine the risk of developing a first myocardial infarction after a hysterectomy and/or oophorectomy. Case-cohort analysis performed among 17,126 women in the Uppsala Health Care Region of Sweden, who had undergone a hysterectomy and/or oophorectomy in 1965 to 1983. Record linkage was used for follow-up and medical records to ascertain the actual history of oophorectomy. Risk estimates were calculated by relating the observed number of cases in the cohort to that expected on the basis of incidence rates in the population. Overall, 214 cases of myocardial infarction were observed. In premenopausal women a bilateral oophorectomy alone tended to increase the relative risk 1.6; 95% CI 0.8-3.1, but this operation combined with hysterectomy increased the risk only among those aged 50 and over at surgery. Hysterectomy at premenopausal age or unilateral oophorectomy did not alter the risk of myocardial infarction. In naturally menopausal women, hysterectomy-mainly for uterine myoma-was associated with a four-fold increase in relative risk (3.8; 95% CI 1.9-7.8). Hysterectomy for treatment of myoma performed after a natural menopause is linked to an excess risk for myocardial infarction. Bilateral oophorectomy before menopause may increase the risk of myocardial infarction.     

Characteristics relating to ovarian cancer risk: collaborative analysis of 12 US case-control studies. II. Invasive epithelial ovarian cancers in white women. Collaborative Ovarian Cancer Group.

Data collected from 2,197 white ovarian cancer patients and 8,893 white controls in 12 US case-control studies conducted in the period 1956-1986 were used to evaluate the relation of invasive epithelial ovarian cancer to reproductive and menstrual characteristics, exogenous estrogen use, and prior pelvic surgeries. Clear trends of decreasing risk were evident with increasing number of pregnancies (regardless of outcome) and increasing duration of breast feeding and oral contraceptive use. Ovarian dysfunction leading to both infertility and malignancy is an unlikely explanation for these trends for several reasons: 1) The trends were evident even among the highly parous; 2) risk among nulliparous women did not vary by marital status or gravidity; and 3) risk among ever-married women showed little relation to length of longest pregnancy attempt or history of clinically diagnosed infertility. Risk was increased among women who had used fertility drugs and among women with long total duration of premenopausal sexual activity without birth control; these associations were particularly strong among the nulligravid. No consistent trends in risk were seen with age at menarche, age at menopause, or duration of estrogen replacement therapy. A history of tubal ligation or of hysterectomy with ovarian conservation was associated with reduced ovarian cancer risk. These observations suggest that pregnancy, breast feeding, and oral contraceptive use induce biological changes that protect against ovarian malignancy, that, at most, a small fraction of the excess ovarian cancer risk among nulliparous women is due to infertility, and that any increased risk associated with infertility may be due to the use of fertility drugs.     

Influence of menstrual and reproductive factors on ovarian cancer risk in women with and without family history of breast or ovarian cancer

BACKGROUND: As women with a family history of ovarian and/or breast cancer possibly inherit genetic changes that alter their risk of ovarian cancer, other established risk factors for ovarian cancer may influence the risk differently in women with and without a family history of the disease. METHODS: Case-control study conducted between 1983 and 1991 in Northern Italy. Cases were 971 women, under 75 years, with incident, histologically confirmed epithelial ovarian cancer, and controls were 2758 women, under 75 years, admitted to hospitals for non-malignant, non-hormone-related conditions, who had not undergone bilateral oophorectomy. Of these, 93 cases and 139 controls had a family history of ovarian and/or breast cancer. RESULTS: The risk of ovarian cancer increased with irregular menstrual cycles, late age at menopause, natural menopause, nulliparity, never use of oral contraceptives and use of hormone replacement therapy. We computed an 'adult life risk score' (ALRS) considering the combined effect of these factors. Compared to women without a family history and a low ALRS, the OR was 1.7 for women without family history and high ALRS, 1.4 for women with a family history and low ALRS, and 3.5 for women with a family history and high ALRS. CONCLUSIONS: Intervention on selected hormonal risk factors for ovarian cancer might be important for women with a family history of the disease.     

Reproductive factors and risk of myocardial infarction.

The relation of reproductive factors to risk of myocardial infarction in women aged 45-69 years was examined in a case-control interview study carried out in Massachusetts from 1986 to 1990. Each of 858 cases of first myocardial infarction was age-matched with a control from the same precinct of residence. Conditional logistic regression was used to control the matching factors and the major known and suspected risk factors for coronary heart disease. For parous women compared with nulliparous women, the estimated relative risk of myocardial infarction was 1.8 (95% confidence interval (CI) 1.0-3.3). Among parous women, the relative risk estimate for five or more births relative to fewer births was 1.4 (95% CI 1.0-2.0); the estimate for a first birth before age 20 relative to a later age at first birth was 1.7 (95% CI 1.1-2.6). The greatest increase in risk was observed for women who had both an early age at first birth and five or more children. However, confounding by factors related to socioeconomic status may have contributed to the results. Compared with women who had a natural menopause at age 50 or older, women who reached the menopause before age 45 were at increased risk regardless of type of menopause: The estimated relative risks were 2.1 (95% CI 1.3-3.2), 1.7 (95% CI 1.0-2.7), and 1.7 (95% CI 1.0-2.8) for early natural menopause, bilateral oophorectomy, and hysterectomy with retention of one or both ovaries, respectively. These results suggest that early cessation of ovulatory function, whether due to natural causes or to surgery, increases the risk of myocardial infarction. Age at menarche was not related to myocardial infarction risk.     

Prophylactic oophorectomy: a historical perspective

Removal of a woman's ovaries (known as bilateral oophorectomy, ovariectomy or, historically, ovariotomy) is undertaken in a number of countries. An estimated 19,000 women aged <60 years had a bilateral prophylactic oophorectomy in the UK in 2003, either as a planned response to an increased specific genetic risk of ovarian or breast cancer or, more frequently, as a prophylactic measure to prevent ovarian cancer. Despite its popularity, however, a full evaluation of the risks, costs and benefits of prophylactic oophorectomy in the absence of genetic markers and at the time of hysterectomy has not yet been undertaken. This paper seeks to provide a historical perspective on current practice by outlining approaches to the ovary in Britain from the 19th century onwards. Historically, ovarian removal has raised many questions about the costs and benefits of surgery. The aim of this article is to highlight the issues, and in so doing, to contribute to a more informed assessment of current practice.     

Age-specific hysterectomy and oophorectomy prevalence rates and the risks for cancer of the reproductive system.

A sample survey was conducted in 1982 to determine the prevalence of hysterectomy and oophorectomy among upstate New York women, ages 25-74. The effects of this surgery on age-specific estimates of the risk for cancer of the uterus, cervix, and ovary were calculated. Overall, 16.9 per cent of the women reported having had a hysterectomy and 9.9 per cent reported a bilateral oophorectomy. The adjustment for age-specific hysterectomy increased the 1977-1979 average annual incidence rate of cervical and uterine cancer by 21 per cent. In several five-year age categories, the increase reached 54 per cent. The 1977-1979 average annual incidence rate of ovarian cancer increased by 12 per cent after adjusting for age-specific bilateral oophorectomy. The increase reached 29 per cent in one five-year age group. The sample results show a lower prevalence of hysterectomy among women 25 to 40 years old and among women 70 to 74 than estimates based on the application of mathematical models to data on surgical incidence.     

Personal and environmental characteristics related to epithelial ovarian cancer. II. Exposures to talcum powder, tobacco, alcohol, and coffee

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.     

Psychosocial correlates of intention to undergo prophylactic oophorectomy among women with a family history of ovarian cancer

BACKGROUND: The purpose of this study was to examine sociodemographic and psychosocial correlates of intention to undergo prophylactic oophorectomy among women with a family history of ovarian cancer. METHODS: Participants were 76 women enrolled in a familial cancer risk assessment program. Psychosocial assessments were collected upon entry into the program and included measures of perceived risk of developing ovarian cancer, perceived benefits and limitations of prophylactic oophorectomy, and psychological distress. In addition, respondents were asked whether they intended to undergo prophylactic oophorectomy in the following 12 months. RESULTS: Thirty-four percent reported intention to have surgery within 12 months. Logistic regression analyses indicated that intention to undergo surgery was associated with several psychosocial factors including greater perceived risk of developing ovarian cancer and greater perceived benefits of surgery. CONCLUSIONS: Women who have heightened risk perceptions and who perceive there to be many benefits of surgery may be more inclined to undergo the procedure, possibly without fully considering the potential limitations and consequences of surgery. These findings suggest the need for education and risk counseling designed to facilitate informed decision making among not only high-risk women, but also women who perceive themselves to be at increased risk.     

Reproductive Risk Factors for Epithelial Ovarian Cancer According to Histologic Type and Invasiveness

PURPOSE: Differences in histology among the subtypes of epithelial ovarian tumors suggest possible differences in their etiologies. We examined reproductive risk factors for epithelial ovarian cancer according to histologic subtype and tumor invasiveness.

METHODS: We conducted a population-based, case-control study of associations between reproductive risk factors and epithelial ovarian cancer in the Delaware Valley from 1994 to 1998. Cases age 20 to 69 years with a recent diagnosis of epithelial ovarian cancer (n = 767) were compared to community controls (n = 1367) frequency matched by age.

RESULTS: With few exceptions, we found significant risk reduction for each histologic subtype of epithelial ovarian cancer by using oral contraceptive, bearing children, and having a tubal ligation; for each subtype, there was significant increased risk associated with a family history of the disease. There were no significant differences among histologic subtypes in the magnitude of the odds ratios for OC use, parity, breastfeeding, tubal ligation, hysterectomy, family history of breast or ovarian cancer, use of noncontraceptive estrogens, age at menarche, and age at menopause. There were also few differences between invasive and borderline tumors, except that women with borderline tumors were significantly younger than women with invasive disease (44.7 years vs. 52.0 years, p < 0.001). Among serous tumors only, women with borderline tumors were more likely to use oral contraceptives than women with invasive tumors (OR = 2.28 95% CI 1.20–4.35).

CONCLUSION: The results of this study suggest that reproductive risk factors do not differ among histologic subtypes of epithelial ovarian cancers.     

Bilateral oophorectomy trends in Olmsted County, Minnesota, 1950-1987

Over the 38-year period from 1950 through 1987, 1,434 Olmsted County, Minnesota women had a first unilateral oophorectomy, while 1,828 underwent bilateral oophorectomy (including 113 with a second unilateral oophorectomy). Most procedures (61% of unilateral and 87% of bilateral oophorectomies) were in conjunction with hysterectomy, and trends over time paralleled those reported for hysterectomy. Almost half of all operations (27% of unilateral and 63% of bilateral oophorectomies) were elective. The rise in bilateral oophorectomy rates over time (3.7 per 100,000 person-years per year, P = 0.016) was mostly due to elective procedures among older women, with both an increased frequency of surgery and a shift from unilateral to bilateral oophorectomy.