Oral contraceptives and neoplasia: 1987 update

[13C]Aminopyrine breath test detects altered liver metabolism caused by low-dose oral contraceptives

The [13C]aminopyrine breath test measures hepatic mixed function oxidase activity. The cumulative percent dose recovered over 2 hr is a sensitive indicator of hepatic dysfunction; values < or = 7.0% have been shown to indicate severe liver disease. Previous studies have suggested that the test results may be influenced by the use of oral contraceptives steroids. We compared the results from five non-oral contraceptive-using women with those from 31 women whose duration of oral contraceptive steroid usage ranged from 4 to 204 months. The women were taking one of four oral contraceptive formulations that differed in the amounts of estrogen (20, 35, or 50 micrograms with 1 mg progesterone) and progesterone (35 micrograms estrogen with stepped levels of progesterone of 0.5, 0.75, and 1.0 mg). The [13C]aminopyrine breath test was performed on days 21 and 28 of the menstrual cycle. Cumulative percent dose recovery values among the normal menstrual cycle of non-oral contraceptive steroid-using women were 12.1 +/- 1.6 and 11.8 +/- 1.5% (mean +/- SD). In contrast, oral contraceptive steroid users showed a marked reduction in cumulative percent dose recovery at 21 days, averaging 6.1 +/- 2.3% (P < 0.001), and returned to normal values (10.2 +/- 3.5%) at 28 days in most women(seven days after oral contraceptive steroid usage was paused). The adverse impact on hepatic mixed function oxidase by oral contraceptive formulations did not differ on the basis of estrogen or progesterone content. The adverse impact of oral contraceptive usage on the mixed function oxidase activity measured by the [13C]aminopyrine breath test must be considered for women of childbearing potential.

Modulatory influence of oral contraceptive pills Ovral and Noracycline on 3-methylcholanthrene-induced carcinogenesis in the uterine cervix of mouse

The present study reports the modulatory influences of combined oral contraceptive formulations, Ovral (0.05 mg ethinylestradiol plus 0.5 mg norgestrel per pill) and Noracycline (0.05 mg ethinylestradiol plus 0.1 mg lynestrenol per pill), on methylcholanthrene (MCA)-induced carcinogenesis in the uterine cervix of Swiss albino mouse. Placement of cotton thread impregnated with beeswax containing approximately 300 micrograms of MCA yielded cervical tumors in 0.0%, 8.6% and 26% animals, respectively, in 30, 60 and 90 days. Concomitant treatments with doses D1 (1/2000th of a pill), D2 (1/200th of a pill) and D3 (1/20th of a pill) of Ovral yielded cervical tumors in 0.0%, 0.0% and 4.5% mice at 30 days, 0.0%, 6.2% and 10% mice at 60 days and in 3.3% (P less than 0.05), 3.4% (P less than 0.05) and 47% mice at 90 days, respectively. Likewise, concomitant treatments with doses D1 (1/2000th of a pill), D2 (1/200th of a pill) and D3 (1/20th of a pill) of Noracycline yielded cervical tumors in 0.0%, 0.0%, 16.6% mice at 30 days, 4%, 3.7% and 54% (P less than 0.05) mice at 60 days and 3.2% (P less than 0.05), 20% and 63% (P less than 0.05) of mice at 90 days, respectively. Both Ovral and Noracycline displayed biphasic action on MCA-induced cervical carcinogenesis in mice. At lower dose levels (D1 and D2), they were inhibitory while at the higher dose level (D3) they were augmentatory in their actions. Both pills also significantly enhanced the incidence of cervical hyperplasia.

Hepatobiliary complications of oral contraceptives

Complications secondary to the use of oral contraceptive agents are rare. Hepatobiliary complications, while often dramatic in presentation, occur infrequently. In a patient without predisposing conditions to complications, the benefits achieved with estrogen/progesterone products outweigh the risks. Those conditions that would absolutely and relatively contraindicate the use of oral contraceptives are listed in Table 4. Patients with a past history of liver disease in whom liver function tests have returned to normal may tolerate the introduction of oral contraceptives. They need to be monitored closely for adverse reactions. Patients who have experienced cholestatic jaundice of pregnancy should avoid all contraceptives because of a high risk of disease recurrence. Women whose first-degree relatives have experienced cholestasis of pregnancy or oral contraceptive-induced cholestasis may be at increased risk and should be closely monitored while taking birth-control pills. Women with current or previous benign or malignant hepatic tumors should not take oral contraceptives. Active hepatitis is an absolute contraindication to using birth control pills, although patients with a past history of hepatitis and no evidence of active disease can have a trial of these drugs with close follow-up. A final group of women who should avoid oral contraceptives is those with familial defects of biliary excretion, including the Dubin-Johnson syndrome, Rotor's syndrome, and benign intrahepatic recurrent cholestasis. Dubin-Johnson syndrome is often asymptomatic and may manifest only during pregnancy or during the use of oral contraceptives. The reduction in hepatic excretory function induced by the sex steroids can transform the mild hyperbilirubinemia into frank jaundice. Oral contraceptive agents are the most widely used reversible means of birth control currently available. Fortunately, the complications associated with these drugs are infrequent and may be decreasing due to lower-dose products. Complications still occur, however, and need to be recognized by the general internist as medication-induced problems so the offending drugs can be discontinued and appropriate treatment and follow-up initiated. In addition, patients at risk for the development of complications need to be recognized and advised prior to the introduction of oral contraceptives.

Contraceptive steroids and the mammary gland: is there a hazard?--Insights from animal studies

The safety of synthetic steroid hormones to be used for contraception in the human female is tested in rats, beagle dogs, and (once marketing starts) in monkeys. Because early studies did not show a mammary tumor stimulating effect in the human, in contrast to findings in the dog, many objections have been raised to the use of the dog for these toxicity studies. It has been claimed that the dog is unique in its sensitivity to the mammary tumor promoting effect of progestins and that this tumorigenic effect results from progestin-induced growth hormone (GH) induction. A thorough review of the literature does not support these claims. Tumor stimulatory effects of progesterone or synthetic progestins can be observed under some conditions in rodents as well as in cats and monkeys. In addition, recent evidence suggests a role for progesterone in mammary tumorigenesis in the human, and contraceptive steroids may also not be completely without risk. While the suggested role for GH in dog mammary tumorigenesis is far from proven, such a role cannot be excluded in the other species. Whether tumor stimulatory effects of sex steroids are based upon induction of proliferation in target cells or upon genotoxic effects or both is not yet certain.

Oral contraceptives and breast cancer. A review with some comments on mathematical models

The relationship between oral contraceptive use and breast cancer is discussed on the basis of information given in review articles, meta-analyses and editorials emphasizing methodological problems related to bias and confounding. Over the last few years a shift in opinion has taken place. Most reviewers now consider that long-term use of oral contraceptives is associated with an increased risk of premenopausal breast cancer and no effect among postmenopausal breast cancer. This result is compatible with an additive effect (in rate measure scale) of oral contraceptive use on breast cancer risk.

Oral contraception in disease states

Oral contraceptives are clearly contraindicated in patients with a history of thromboembolic disease, ischemic heart attack, or cerebral stroke. Patients requiring long-term anticoagulant treatment can be treated with gonadotropin-releasing hormone analogs to prevent ovulation, because ruptured follicles can cause massive intraperitoneal bleeding. Patients with essential hypertension and severe liver diseases should also discontinue treatment 4 weeks before major elective surgery. Migraine and diabetes mellitus are regarded as relative contraindications, depending on the individual situation. Long-term diseases, such as Crohn's disease, epilepsy, and sickle cell anemia, also require individualized consultation.

Safety of intrauterine contraception

Some of the risks which have been associated with the use of intrauterine contraception are reviewed. For users of copper-releasing IUDs, such as the Multiload Cu375 and TCu380, uterine perforations are rare, there is no evidence of an increased risk of infertility, and there probably is no increased risk of ectopic pregnancy after IUD removal. Any increased risk of pelvic inflammatory disease may be limited to the initial months of IUD use. The safety of intrauterine contraception needs to be re-evaluated for the newer IUDs, since most of the information relating to IUD safety is based on studies of devices which are no longer used or which are not in widespread use.

Contraception in the adolescent. Preparation for the 1990s

An overview of current and future contraceptive methods available to the adolescent is presented. Emphasis is given to oral contraceptives, including low-dose monophasics and triphasics. Current research confirms the efficacy and safety or oral contraceptives for teenagers. Other methods are reviewed, such as the mini-pill, barrier contraceptives (including the cervical cap and female condom), injectable contraceptives, hormonal contraceptive implants, the vaginal ring, postcoital contraception, periodic abstinence, gossypol, and others. Though abstinence is the best contraceptive method for adolescents, contraceptive technology of the 1990s presents clinicians and sexually active youth with many additional options.

Correlation between peripheral CA-125 levels and ovarian activity

Serum CA-125 concentrations were measured at three different times in normal cycles, pill-suppressed cycles, and cycles stimulated for intrauterine insemination (IUI) or oocyte retrieval, i.e., (1) during the first half of the cycle, (2) at midcycle or at the moment of oocyte retrieval, and (3) the second half of the cycle. Significant variations of serum CA-125 concentrations were not seen during the cycle in normally cycling women or in women taking oral contraceptives: mean +/- SD 28.9 +/- 13.3 U/mL and 26.9 +/- 11.3 U/mL, respectively. In patients stimulated for in vitro fertilization, luteal phase CA-125 levels (60.6 +/- 38 U/mL) were significantly higher than during stimulation (21.5 +/- 5.9 U/mL) or at oocyte retrieval (19.6 +/- 6.4 U/mL). In stimulated cycles for IUI, without laparoscopy or follicular puncture, a comparable rise of CA-125 was observed in the luteal phase (49.6 +/- 37.8 U/mL). However, in patients undergoing laparoscopic sterilization, serum CA-125 concentrations before and after laparoscopy were not significantly different (22.8 +/- 6.3 U/mL and 25 +/- 4.2 U/mL, respectively).

Persisting cyclical uterine bleeding in patients treated with radical radiation therapy and hormonal replacement for carcinoma of the cervix

Radical radiation therapy used for carcinoma of the cervix will ablate ovarian function. Since January 1986, our policy has been to administer oral combination oestrogen-progesterone replacement hormonal therapy to all premenopausal patients undergoing radical radiation with or without synchronous chemotherapy, for invasive cervix cancer. Five out of 22 (23%) such patients unexpectedly experienced between one and four episodes of cyclical per vaginal bleeding after the completion of radiation therapy. Bleeding episodes occurred in the absence of persistent tumor or radiation reaction, and suggest persisting endometrial response to exogenous hormonal stimulation. Uterine activity was temporarily retained in these five patients despite a minimal endometrial surface dose of between 4800 and 6490 cGy. The limited number of cycles before bleeding spontaneously ceased may represent the slow death of endometrial cells subsequent to radiation or radiochemotherapy treatment, and has not previously been described. In view of the paucity of data on the radiosensitivity of normal endometrium, we have carefully examined these patients who appear to have retained endometrial sensitivity to hormonal stimuli after radical radiation-chemotherapy for uterine cervix cancer.

Oral contraception: risks and benefits

Data on the risks and benefits of using the oral contraceptive continue to accumulate. Because of continuing changes in the formulation and dosage of both the estrogens and progestins, the medical community must constantly re-evaluate all older data when considering current risk/benefit ratios. The changes in pill formulation have led to increased acceptability with a reduction of both nuisance and serious long-term side effects. The risks must be balanced against the major contraceptive and non-contraceptive benefits that are provided by the pill. Although both the benefits and risks have been documented in the literature, both the physician and the patient are being overwhelmed by press reports stressing mainly the negative aspects of the pill. It is incumbent on all physicians to periodically review the sources and validity of all medical reports on the pill. While the benefits of the pill outweigh the risks, the physician must be constantly aware of the changing world literature in order to optimize his/her prescribing patterns.

Hormonal contraception

Increased sexual activity among adolescents demands that the health care provider have a thorough understanding of contraceptive methods and application. In this article, the principles of hormonal contraception are discussed, providing relevant information for use in advising and managing the sexually active adolescent.

Contraception for women exposed in utero to diethylstilbestrol

Although the effects of in utero exposure to diethylstilbestrol (DES) have been extensively documented, there is an absence of information on the suitability of different contraceptives for use by DES-exposed women. This paper briefly describes some of the effects associated with DES exposure. Use of various contraceptive methods by DES-exposed women are considered in light of these effects.

Liver tumours

Humans are remarkably resistant to many carcinogens that readily produce liver tumours in rodents, particularly the rat. The neoplastic process has been extensively studied in animal experiments, but little is known so far of how it evolves in humans. Few drugs have been shown to cause liver tumours in humans, and the risk appears to be low. The best-known examples are C17-alkylated or ethinylated gonadal sex steroids. Oral contraceptives have now been in use by millions for thirty years, but only a few hundred cases at most of liver cell adenoma have been observed. The role of these substances in liver cell carcinoma remains controversial, and the evidence is weaker still in relation to focal nodular hyperplasia and other tumour-like conditions. Anabolic-androgenic steroids stand out as the major cause of peliosis, but liver cell tumours induced by them seem to be adenomas and not carcinomas as originally suggested. The effect that both oral contraceptives and anabolic-androgenic steroids have on liver vasculature is of great clinical importance as the most important complication of liver tumours is rupture, leading to life-threatening haemorrhage. For this reason, liver tumours arising in users of these drugs should be removed whenever feasible. Thorium dioxide will remain a risk factor for the development of angiosarcoma, liver cell carcinoma and bile duct carcinoma for some time yet, and the number of patients who have been exposed is high--tens of thousands at least. The evidence of a carcinogenic role for many other drugs is anecdotal or weak. Neoplasia in the liver seems to be the least important side-effect of drugs in clinical use.