Howard W. Ory

Complications of abdominal and vaginal hysterectomy among women of reproductive age in the United States. The collaborative review of sterilization

Although hysterectomy was the most frequently performed major surgical procedure among women of reproductive age during the past decade, few recent studies have been conducted to determine the risk of complications. We examined data from the Collaborative Review of Sterilization, a prospective, multicenter, observational study coordinated by the Centers for Disease Control, to assess the comparative risks of complications among women undergoing hysterectomy by the abdominal and vaginal approaches. Between September, 1978, and August, 1981, 1,851 women from nine institutions were included in the study. Women who underwent vaginal hysterectomy experienced significantly fewer complications than women who had undergone abdominal hysterectomy. The difference was probably attributable to the prevalence and efficacy of prophylactic antibiotic use among the former group. Vaginal hysterectomy was associated with more unintended major surgical procedures but less febrile morbidity, bleeding requiring transfusion, hospitalization, and convalescence than abdominal hysterectomy. Vaginal hysterectomy with prophylactic antibiotics should be strongly considered for those women of reproductive age for whom either surgical approach is clinically appropriate.

The independent associations of parity, age at first full term pregnancy, and duration of breastfeeding with the risk of breast cancer

Although the important influence of a womans reproductive history on her risk of breast cancer is widely recognized, it is not clear whether this is wholly accounted for by the age at her first full-term pregnancy, or whether there are additional, independent influences of breastfeeding or number of children. To examine the respective contributions to the risk of breast cancer of these reproductive factors, we used logistic regression methods to analyze data from a multicenter case-control study, the Cancer and Steroid Hormone Study. Included in the analysis were 4599 women, 20-55 years of age, identified as having an initial diagnosis of breast cancer by one of eight collaborating population-based cancer registries. The 4536 controls were women of similar ages selected by random dialing of households with telephones in the same eight areas. As expected, age at first full-term pregnancy exerted a strong influence on the risk of breast cancer. However, after it and other potentially confounding factors had been controlled for, parity and duration of breastfeeding also had a strong influence on the risk of breast cancer. Compared with women of parity one, women of parity seven or greater had an adjusted relative risk of breast cancer of 0.59 (95% CL, 0.44-0.79). Compared with parous women who never breastfed, women who had breastfed for 25 months or more had an adjusted relative risk of 0.67 (0.52-0.85). These results do not support the supposed preeminent importance of age at first full-term pregnancy among the reproductive determinants of breast carcinogenesis. Resolution of this issue may have important implications for elucidating hormonal influences on breast cancer and for projecting future trends in the disease.

The Reduction in Risk of Ovarian Cancer Associated with Oral-Contraceptive Use

Although several studies have reported that the use of oral contraceptives decreases the risk of ovarian cancer, it is not clear whether the effect varies according to the oral-contraceptive formulation or the histologic type of cancer. To characterize this association more fully, we used data from a case-control study, the Cancer and Steroid Hormone Study. From 1980 to 1982, 546 women 20 to 54 years of age with ovarian cancer were enrolled from eight population-based cancer registries. The controls were 4228 women selected from the same areas. Women who had used oral contraceptives had a risk of epithelial ovarian cancer of 0.6 (95 percent confidence interval, 0.5 to 0.7) as compared with those who had never used them. This protective effect was seen in women who had used oral contraceptives for as little as three to six months, and it continued for 15 years after use ended; it was independent of the specific oral-contraceptive formulation and of the histologic type of epithelial ovarian cancer. (We could not adequately assess the association with nonepithelial ovarian cancers because of an insufficient number of cases.) We conclude that the use of oral contraceptives decreases the risk of epithelial ovarian cancer.

The mortality risk associated with hysterectomy.

To study the risks of mortality associated with hysterectomy that are specific to age, race, surgical approach, and associated conditions, we used data collected by the Commission on Professional and Hospital Activities during 1979 and 1980. Four hundred seventy-seven deaths were recorded among 317,389 women having abdominal hysterectomies and 46 deaths among 119,972 women having vaginal hysterectomies. The mortality rates for hysterectomy, standardized for age and race, were higher for procedures associated with pregnancy or cancer than for procedures not associated with these conditions (29.2, 37.8, and 6.0 per 10,000 procedures, respectively). Hysterectomies associated with pregnancy or cancer constituted 8% of all hysterectomies performed. However, 61% of all deaths occurred in women with pregnancy- or cancer-related conditions. The mortality rate associated with hysterectomy increased with age and was twice as high among black women.

Confirmation of the preoperative diagnoses for hysterectomy.

Few previous studies have examined the relationship between the preoperative and pathologic diagnoses for hysterectomy. To determine the percentage of preoperative diagnoses that were confirmed by pathologic examination, we analyzed data from the Collaborative Review of Sterilization, a multicenter study of hysterectomies and tubal sterilizations in women aged 15 to 44 years. Data were collected from patient interviews and chart reviews. Of the 1851 women included in this study, 1283 (69%) had abdominal hysterectomies and 568 (31%) had vaginal hysterectomies. Overall, 52% of the hysterectomies were performed for a preoperative diagnosis that could potentially be confirmed by pathologic examination. Pathologic examination actually confirmed the preoperative diagnosis of endometrial hyperplasia in 95% of the cases, cervical intraepithelial neoplasia in 89%, leiomyomas in 84%, pelvic inflammatory disease in 75%, adenomyosis in 48%, and endometriosis in 47%. Among all of the potentially confirmable diagnoses, 80% were confirmed. The remaining 48% of the women who had hysterectomies had preoperative diagnoses that were not amenable to confirmation by pathology. Most of these were for one of three diagnoses: menstrual bleeding disorders, pelvic pain, or pelvic relaxation. In 47% of these cases, pathologic examination showed leiomyoma or adenomyosis; no abnormalities were found in 38% of these cases.

Oral contraceptives and pelvic inflammatory disease

To study the association of the use of oral contraceptives and pelvic inflammatory disease (PID), we analyzed data from a large multicenter case-control study of contraceptive use and serious gynecologic disorders. The analysis included data from interviews of 648 women hospitalized with an initial episode of PID and 2,516 hospitalized control subjects. The risk of PID for women using oral contraceptives in the 3 months prior to interview was 0.5 (95% confidence limits, 0.4 to 0.6) relative to women using no contraceptive method during this period. This association was not explained by differences between case subjects and control subjects in demographic variables, level of sexual activity, or medical history. The protective effect of current oral contraceptive use against PID was restricted to women using oral contraceptives for more than 12 months; past use of oral contraceptives did not exert a protective effect against PID. Annually, an estimated 50,000 initial cases of PID are prevented by oral contraceptive use; 12,500 hospitalizations are also averted by oral contraceptive use. Consequently, protection against PID is one of the most important noncontraceptive benefits of oral contraception.

Deaths attributable to tubal sterilization in the United States, 1977 to 1981

In 1979, the Centers for Disease Control began surveillance of deaths attributable to tubal sterilization in order to determine why they occur and what may be done to prevent them. Since that time, 29 such deaths have been identified as occurring in the United States from 1977 through 1981. Of these 29 deaths, 11 followed complications of general anesthesia, seven were due to sepsis, four were due to hemorrhage, three were due to myocardial infarction, and four deaths were related to other causes. Some of these deaths might have been prevented by use of endotracheal intubation for general anesthesia, particularly for laparoscopic sterilization, safer use of unipolar coagulation or use of alternative techniques, careful insertion of the needle and trocar for laparoscopy, and discontinuation of oral contraceptives before sterilization. Further surveillance may help to make tubal sterilization even safer.

The intrauterine device and deaths from spontaneous abortion.

To evaluate the intrauterine device as a risk factor for mortality associated with spontaneous abortion, we analyzed all deaths from spontaneous abortions reported in the period 1972-1974. Women dying from spontaneous abortions with a device in place were more likely to be young, white and married than those not wearing a device. Risk of death from spontaneous abortion was over 50 times greater for women who continued their pregnancy with a device in place than for those who did not. The Dalkon shield carried an increased risk of death, as compared to other devices, even after rates were adjusted for duration of use. However, pregnant women with either a loop or a coil in place also had a higher risk of dying from spontaneous abortion than those without any device. The results support the clinical recommendation that any device should be removed when pregnancy is first diagnosed.

Oral-contraceptive use and the risk of breast cancer. The cancer and steroid hormone study of the centers for disease control and the national institute of child health and human development

To investigate the effect of individual formulations of oral contraceptives on the risk of breast cancer in women, we analyzed case-control data from the Cancer and Steroid Hormone Study of the Centers for Disease Control. The cases were 4711 women 20 to 54 years old with newly diagnosed breast cancer who were selected from eight population-based cancer registries. The controls were 4676 women selected by random-digit dialing of the population of each area covered by a registry. As compared with women who had never used oral contraceptives, women who had used them had a relative risk of breast cancer of 1.0. Among women who used only one oral-contraceptive formulation, this estimate of relative risk did not change appreciably according to the formulation used. Neither the type of estrogen nor the type of progestin contained in oral contraceptives used was associated with an increased risk of breast cancer. The duration of oral-contraceptive use and the time since last use did not influence the risk. These findings provide further support for the contention that oral-contraceptive use does not increase the risk of breast cancer in women.

The noncontraceptive health benefits from oral contraceptive use.

Studies have documented the protective effects of oral contraceptives (OCs) against 5 diseases: 1) OCs prevent 50-75% of potential cases of benign breast disease; there is an estimated annual reduction of 235 hospitalized cases for every 100,000 U.S. women using OCs or about 20,000 hospitalizations each year. 2)OCs reduce the occurrence of retention cysts of the ovary; an estimated 3000 surgical procedures for ovarian cysts are prevented each year in the U.S. 3) OC users have approximately 45% less iron-deficiency anemia than nonusers due to less menstrual flow. 4) OCs protect against the development of pelvic inflammatory disease (PID); 600 of every 100,000 OC users are prevented from contracting a 1st episode of PID and 156 PID hospitalizations are averted for every 100,000 OC users annually. 5) OCs protect against ectopic pregnancy; approximately 120 hospitalizations/100,000 users are prevented annually. 3 additional diseases may be prevented by OCs, although the evidence is not as conclusive as for the 5 previously discussed; OC users are only 1/2 as likely to develop: 1) rheumatoid arthritis, 2) endometrial cancer, and 3) ovarian cancer as nonusers. OCs have also been shown to reduce the incidence of such disorders as excessive menstrual bleeding, irregular menses, intermenstrual bleeding, painful menstruation, and premenstrual tension.