RESUMO
Studies on the introduction of Cyclofem into family planning programmes have been undertaken in Indonesia, Jamaica, Mexico, Thailand and Tunisia. Cyclofem is a once-a-month injectable contraceptive containing 25mg medroxyprogesterone acetate and 5mg estradiol cypionate. A total of 7927 subjects were followed in close to routine service delivery conditions in primary and secondary family planning outlets. The studies confirmed the high efficacy of the method with 12-month pregnancy rates ranging from 0 to 0.7%. Major differences were seen in reasons and rates of discontinuation between countries, the overall 12-month life table discontinuation rates ranging from 33.5% in Indonesia to 71.8% in Tunisia. The reasons for discontinuation in each of the five countries are described, differences between countries contrasted, and service delivery issues which should be addressed further, raised.
Assuntos
Anticoncepcionais Femininos/administração & dosagem , Estradiol/análogos & derivados , Serviços de Planejamento Familiar , Acetato de Medroxiprogesterona/administração & dosagem , Adolescente , Adulto , Anticoncepcionais Orais Combinados/administração & dosagem , Anticoncepcionais Orais Combinados/efeitos adversos , Combinação de Medicamentos , Estradiol/administração & dosagem , Estradiol/efeitos adversos , Feminino , Humanos , Indonésia , Injeções , Jamaica , Acetato de Medroxiprogesterona/efeitos adversos , México , Satisfação do Paciente , Projetos Piloto , Gravidez , Tailândia , Tunísia , Organização Mundial da SaúdeRESUMO
Following the development and widespread use of oral hormonal contraceptives, it became evident that alternative long-acting delivery systems would be required to improve contraceptive practice in some cultural settings where injectable or subdermal routes of administration are preferred. Nowadays, long-acting contraceptives constitute an important option in family planning services in many parts of the world. Indeed, two long-acting injectable contraceptives containing just a synthetic progestogen (depot-medroxyprogesterone acetate (DMPA) and norethisterone enantate (NET-EN)) have been in clinical practice for more than 20 years. The World Health Organization's (WHO) Special Programme of Research in Human Reproduction, in collaboration with the U.S. National Institute of Child Health and Human Development (NICHD) and universities primarily in developing countries undertook a synthesis programme aimed at producing an improved injectable preparation by developing new derivatives of known steroids. One such compound (levonorgestrel 17-butanoate) is now at the stage of Phase II clinical testing. In addition, the Special Programme has developed and improved once-a-month injectable formulations and assessed their safety and efficacy in different countries worldwide. After large scale clinical testing, at least two progestogen-estrogen combinations have reached the point of introductory trials.
PIP: A survey of recent trials of new injectable hormonal contraceptives, progestogen-only, levonorgestrel esters, and once monthly injectables, follows a brief review of all the experimental long-acting contraceptive modalities, injectables, implants, vaginal rings, and hormone-releasing IUDs. Currently medroxyprogesterone acetate (DMPA) and norethisterone enanthate (NET-EN) are being used by 7 million women. WHO is conducting dose reduction trials and studies of bioavailability in various national populations. Even though a dose of 100 mg DMPA every 3 months has been satisfactory for contraception, 150 mg is still recommended until further pharmacodynamic data are available. Some populations, notably Thais and Mexican women, have higher peaks and more rapid elimination rates of DMPA, while Chinese women show slower elimination and higher blood levels of NET-EN. Extensive studies of new synthetic esters of levonorgestrel have proceeded to Phase II clinical trials with levonorgestrel butanoate. This ester is an effective contraceptive for 3 months at 12.5 mg, or 5-6 months at a dose of 25 or 50 mg. Trials of combined estrogen and progestogen injectables once-monthly have been ongoing for 10 years. The ratio of the 2 components is as important as the amounts. 2328 women from 12 countries participated in trials of DMPA 25 mg-estradiol cypionate 5 mg, and NET-EN 50 mg-estradiol valerate 5 mg. The continuation rate was better than that for 3-monthly progestogen-only injectables, because of less irregular bleeding. A combined injectable called Cyclofem, DMPA 25 mg-estradiol cypionate is being introduced in several countries. The steadily increasing demand for long-acting injectables prompts development of better formulations.
Assuntos
Anticoncepcionais Femininos/administração & dosagem , Noretindrona/análogos & derivados , Compostos de Anilina/administração & dosagem , Compostos de Anilina/farmacocinética , Anticoncepcionais Femininos/farmacocinética , Preparações de Ação Retardada , Implantes de Medicamento , Feminino , Humanos , Levanogestrel/administração & dosagem , Noretindrona/administração & dosagem , Noretindrona/farmacocinética , Acetato de Noretindrona , Ovulação/efeitos dos fármacosRESUMO
A multicentered study was undertaken at three institutions in Hungary, Mexico and Thailand in women of reproductive age to evaluate the effects of full and half doses of HRP112 (depot-medroxyprogesterone acetate (DMPA) plus estradiol cypionate) and DMPA alone on ovarian function, bleeding patterns and HDL-cholesterol levels. Full dose HRP112 contained 25mg DMPA plus 5mg, of estradiol cypionate and the half dose, 12.5mg DMPA plus 2.5mg of estradiol cypionate. The full and half dose DMPA were 25 and 12.5mg respectively. In all, 88 women were recruited in the study and randomized within each centre, to the four treatment groups. Subjects were studied for a control cycle, three one-month injection intervals and followed-up for a further two months. Serum concentrations of estradiol, progesterone and medroxyprogesterone acetate were determined three times a week during the third injection interval and during the two months of follow-up. While the results from all centres indicated that the four preparations were all effective in inhibiting ovulation for at least one month, there were marked between centre differences in pharmacokinetic profiles. More regular bleeding patterns were observed in women who received the estrogen-progestogen combination preparations than in those who received DMPA alone.