Contraceptive potential

Mifepristone as well as other PAs have contraceptive potential and some encouraging pilot studies have been conducted in unprotected women who relied exclusively on mifepristone for their contraception. Ovulation is inhibited with daily doses of mifepristone of 2 mg or higher. A total of 40 sexually active women in Shanghai and 10 women in Edinburgh were randomly assigned to receive 

A sequential regimen using mifepristone (10 mg) and the progestin nomegestrol acetate (5 mg) was studied in 30 women for 12 consecutive cycles without pill-free days. Mifepristone was administered for 15 days and this was immediately followed by the progestin for 13 days. One pregnancy occurred in 359 woman-months of exposure. This study has been published in abstract form [81, 82], 

Other strategies are based on the observation that mifepristone can retard endometrial development. In two studies, a total of 53 women received 200 mg mifepristone 48 h after the luteinizing hormone (LH) surge and there were only three pregnancies in a total of 335 cycles [83, 84]. In view of its complexity, a method dependent on the precise timing of the LH surge does not represent a practical approach to contraception. 

Weekly administration of mifepristone in doses as high as 25 mg do not consistently inhibit ovulation [85], However, this regimen does interfere with normal endometrial development. No pregnancies occurred when once weekly administration of mifepristone (25 and 50 mg) was given for 6 months to a total of 76 women. There were a total of 456 women-months of use [86]. 

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Theophylline Cimetidine, erythromycin, influenza vaccine, oral contraceptives Potentiation. 

Progestogen-only products do not have inhibition of ovulation as their main effect up to half of all cycles are ovulatory, and the contraceptive potential relates largely to changes in the consistency of the cervical mucus and the creation of a... 

Brown, A., Cheng, L., Lin, S. and Baird, D.T. (2002) Daily low-dose mifepristone has contraceptive potential by suppressing ovulation and menstruation a double-blind randomized control trial of 2 and 5 mg per day for 120 days. Journal of Clinical Endocrinology and Metabolism, 87, 63-70. 

Vaginal Rings. Vaginal epithelium is readily permeable to contraceptive steroids. Since the vascular drainage of the vagina bypasses the Hver, this route of adrninistration potentially permits utilisation of dmgs that have low oral activity. 

Research on an hCG vaccine has been conducted over the past 15 years. WHO has conducted a phase I clinical study in AustraUa, using a vaccine based on a synthetic C-terminal peptide (109—141) of P-hCG conjugated to Diptheria Toxoid (CTP-DT), that showed potentially effective contraceptive levels of antibodies were produced in vaccinated women without any adverse side effects. Phase II clinical studies are under consideration to determine if the immune response, raised to its prototype anti-hCG vaccine, is capable of preventing pregnancy in fertile women volunteers (115). While research on the C-terminal peptide from the P-subunit of hCG has been carried out under the auspices of WHO, research supported by the Population Council and the National Institutes of Health has involved two alternative vaccine candidates (109,116,118). 

Several other antigens with good immunocontraceptive potential have been identified and investigated in laboratory animals. In most studies, the rate and duration of the immunocontraceptive effect are less than acceptable. A potential problem in immunological approaches to antifertUity research is the need for a safe, effective adjuvant and suitable animal models for evaluating the efficacy and safety of methods (111). Newer and more effective adjuvants are required for contraceptive vaccines and vaccines in general. 

Thus, our attention should shift from the concern of potential adverse effects to the health benefits imparted by hormonal contraceptives. The use of oral contraceptives for at least 12 months reduces the risk of developing endometrial cancer by 50%. Furthermore, the risk of epithelial ovarian cancer in users of oral contraceptives is reduced by 40% compared with that on nonusers. This kind of protection is already seen after as little as 3-6 months of use. Oral contraceptives also decrease the incidence of ovarian cysts and fibrocystic breast disease. They reduce menstrual blood loss and thus the incidence of iron-deficiency anemia. A decreased incidence of pelvic inflammatory disease and ectopic pregnancies has been reported as well as an ameliorating effect on the clinical course of endometriosis. 

Statins should not be used in pregnant women. If women with child-bearing potential are treated with statins efficient contraception should be secured. Statins should at present not be used in children unless they carry a very high risk of premature vascular-disease and in this case only by very experienced lipid specialists. 

Women taking the barbituratesor the benzodiazepines should be warned of the potential risk to the fetus so that contraceptive methods may be instituted, if necessary. A child born to a mother taking benzodiazepines may develop withdrawal symptomsduring the postnatal period. 

Whole microbial cells as well as microbially derived enzymes have played a significant role in the production of novel antibiotics. The potential of microorganisms as chemical catalysts, however, was first fully realized in the synthesis of industrially important steroids. These reactions have assumed increasing importance following the discovery that certain steroids such as hydrocortisone have anti-inflammatory activity, whilst derivatives of the steroidal sex hormones are nsefiil as oral contraceptive agents. More recently, chiral inversion of non-steroidal anti-inflammatory dmgs (NS AIDs) has been demonstrated. 

As discussed later in this chapter, contraindications exist for various forms of contraception. Patients must be evaluated completely by a health care professional to rule out any medical contraindications to certain contraceptives. The physical examination also will allow health care professionals to determine if there are other medical concerns, such as hypertension, diabetes, or liver disease, that need to be considered when determining the appropriate contraceptive agent. Clinicians also should review family history for potential risks with certain forms of birth control. 

In addition to preventing pregnancy, there are several noncontraceptive benefits associated with the use of combined oral contraceptive pills. Many of the potential non-contraceptive benefits are highlighted below. 

While there are many non-contraceptive benefits associated with the use of combined oral contraceptives, their use is not without risk or potential for adverse effects. 

As with all medications, there are potential adverse effects with combined oral contraceptives (COCs). Many side effects can be minimized or avoided by adjusting the estrogen and/or progestin content of the oral contraceptive. It is also important to have proper patient selection for oral contraceptives because some women are at increased risk for potentially serious side effects. 

What information can you provide to the patient regarding the potential association between weight gain and oral contraceptive use ... 

Methotrexate 7.S-20 mg once weekly Oral or IM 4-8 weeks N, D, hepatotoxicity, alopecia, new-onset cough or SOB, MYL CBC, creatinine, LFTs q 4-8 weeks Monitor for signs of infection Concomitant use of folic acid Avoid alcohol Use contraception if childbearing potential... 

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