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Contraception. 2006 Feb; 73(2):195-204.The use of progestogen-only contraceptives among women with sickle cell anemia has generated concerns about possible hematological and other clinical complications. Based on the literature, we assessed whether use of progestogen-only contraceptives is associated with adverse health effects among women with sickle cell anemia. We searched the MEDLINE database for articles published in peer-reviewed journals between 1966 and September 2004 that were relevant to sickle cell anemia and use of progestogen-only contraceptives. Of the 70 articles identified through the search, 8 met the criteria for this review. These studies did not identify any adverse events or clinically or statistically significant adverse changes in hematological or biochemical parameters associated with the use of progestogen-only contraceptive methods. Six studies suggested that users experienced a decrease in clinical symptoms and less frequent and severe painful crises compared with nonusers. Although data are limited, these studies suggest that progestogen-only contraceptives are safe for women with sickle cell anemia. (author's)
Geneva, Switzerland, WHO, 1981. 76 p. (WHO Technical Report Series No. 657)This report on the effect of female sex hormones on fetal health and development aimed to evaluate research on the specific types of sex hormones and their uses, to determine their safety with respect to fetal development and infant health, and to recommend further research in these areas. Theoretically, sex hormones can affect any stage of fetal development. Sex hormones appear to act by promoting synthesis of messenger ribonucleic acid (mRNA) in target tissues, so that research should focus on the specific proteins formed under the direction of newly synthesized mRNA to elucidate potential morphological and physiological effects of exogenous hormones. Following are some research avenues: cytogenetic research, microscopic and macroscopic examination, observations on births and later life, animal teratology, and epidemiological studies. Epidemiological studies not only help elucidate causal associations but also provide public health data. Studies of sex hormones and fetal development and infant health must be free of bias and often suffer from problems of defining pregnancy outcome. Also sex steroids are frequently administered at the same time as other drugs, leading to confounding effects of drug interactions. In order to assess existing data, it is necessary to disaggregate the data from different reports and then to regroup them according to the indications for use, i.e., infertility, contraception, pregnancy testing, supportive therapy during pregnancy, contraception during pregnancy, contraception during breast feeding. Likewise data must be disaggregated according to different types of exposure, i.e., preconception or postconception. The bulk of this monograph is spent disaggregating study data based on the above-stated rationales. The following recommendations are made for indications for use of sex hormones: 1) they should not be used as pregnancy tests; 2) diethylstilbestrol should not be prescribed to a suspected pregnant woman; 3) benefits of progestin therapies must first be proven before they can be recommended for use in supporting pregnancy; 4) oral contraceptives given before pregnancy seem to have no effect on subsequent pregnancy; and during lactation combined therapy should not be given.
WHO Scientific Group Meeting on Cardiovascular Disease and Steroid Hormone Contraceptives. Reunion du Groupe scientifique OMS sur les maladies cardio-vasculaires et les contraceptifs hormonaux steroidiens.
WEEKLY EPIDEMIOLOGICAL RECORD. 1997 Nov 28; 72(48):361-3.More than 100 million women worldwide are thought to use steroid hormone contraceptive methods, with an estimated 93 million women using combined oral contraceptives (COCs). The composition and use of these contraceptive preparations, especially those of COCs, have changed dramatically over the years. The World Health Organization (WHO) convened a Scientific Group Meeting on Cardiovascular Disease and Steroid Hormone Contraception during November 3-7, 1997, to review current scientific data on the use of steroid hormone contraception as they relate to the risk of myocardial infarction, ischemic and hemorrhagic stroke, and venous thromboembolic disease. The group also reviewed the incidence of cardiovascular disease among women of reproductive age in general, how the effect of risk factors for cardiovascular disease may be changed using hormonal contraceptives, and whether different compositions of COCs have different cardiovascular risk profiles. The group was comprised of the authors of background papers prepared for the meeting and experts from around the world. The scientific group's conclusions are presented. The incidence and mortality rates of all cardiovascular diseases are very low among reproductive-age women. For women who do not smoke, who have their blood pressure checked, and who do not have hypertension or diabetes, the risk of myocardial infarction in COC users is not increased regardless of age. While current users of COCs have a low absolute risk of venous thromboembolism, their risk is still 3-6 times greater than that of nonusers, with the risk probably being highest during the first year of use.
[Contraception via a vaginal hormonal ring] Kontratseptsiia posredstvom vlagalishten khormonalen prusten.
AKUSHERSTVO I GINEKOLOGIIA. 1991; 30(1):49-52.Research on the hormonal vaginal ring began in the US in 1973. Its prototype with a diameter of 55 mm releasing in even doses small amounts of hormone was introduced 17 years later. Its high effectiveness with a failure rate of 3-4 pregnancies/100 woman use years is similar to that of most IUDs. The first type contains a combination of estrogen-gestagen consisting of levonorgestrel and 17-beat-estradiol as in oral preparations. It has to be used from the beginning of the menstrual cycle for 3 weeks and removed for 1 week. The second one, devised by a special program of WHO, contains gestagen only in the form of levonorgestrel (LNG) releasing 20-25 mcg of LNG daily. The third type contains progesterone only which is suitable for use by lactating women, as the progesterone eventually absorbed in the maternal system does not pose any risk to the nursing child. At present its effectiveness is being tested, and then its practical application will be examined. The introduction of the prototype was delayed by 2 years when initial investigations showed that the substance used for polymerization of the plastic used for the vaginal ring was carcinogenic, however, this was refuted in subsequent investigations. The vaginal ring is already sold regularly in Great Britain and in some western European countries. This new method allows doctors to provide an alternative contraceptive in addition to the existing ones.
PROGRESS IN HUMAN REPRODUCTION RESEARCH. 1992; (22):8.The WHO Special Programme on Research, Development and Research Training in Human Reproduction and diagnostic companies conduct research into the development of a simple, accurate, robust, home based method which predicts ovulation. A prolonged rise in the excretion product of estradiol in the uterine indicates that ovulation will soon follow A similar rise in serum estradiol levels also occurs several days before ovulation. Researchers in Melbourne, Australia have created an uncomplicated tool to measure the most plentiful estradiol excretion product, estrone glucuronide, and the progesterone excretion product, pregnanediol glucuronide, whose rising levels indicate the end of the fertile period. In 1991, WHO and the Australian researchers began a multicenter studying comparing this instrument with the sign and symptoms observed in traditional natural family planning methods. As of mid 1992, results were not yet available. The ability to determine the beginning and the end of the fertile period makes this potential tool especially promising. WHO is supporting another multicenter study testing for a decline of the enzyme guaiacol peroxidase in cervical mucus as a marker of approaching ovulation. It is difficult to test for forthcoming ovulation in premenopausal women, because they do not always ovulate their menstrual cycles. A WHO study looked at the association between ovarian hormone secretion an symptothermal indicators of fertility in 36 premenopausal women (177 menstrual cycles). Around 33% of the women regular menstrual cycles that may have been fertile, around 19% experienced no hormonal changes indicating fertility during their cycles, and the rest of the woman had a combination of both. Further traditional symptothermal markers could not distinguish the 2 different types of cycles.
Progesterone-releasing vaginal rings for use in postpartum contraception. I. In vitro release rates of progesterone from core-loaded rings.
CONTRACEPTION. 1992 Apr; 45(4):329-41.Chemists from London, England and a chemist from WHO in Geneva, Switzerland compared release rates of progesterone from vaginal rings with cores of different diameters (4, 5, 6, 6.7, and 7.24 mm). The manufacturer loaded each core with 25% w/w progesterone. The technique used to dissolve the progesterone from the silicone rubber core consisted of placing the rings in continuously flowing baths of isotonic saline at 37 degrees Celsius. The learned that a membrane diffusion controlled process, modified by the development of a gradually increasing zone of depletion at the core surface, did indeed release the progesterone. The used the UV absorption method to measure the amount of progesterone released in 24 hour periods for as much as 128 days. The vaginal ring with the 6 mm core released 3.6-5.5 mg progesterone/day in a 90 day period. The daily range of maximum and minimum values for each set of rings demonstrated good reproducibility. Progesterone release was inversely related to diffusion distance (between core surface and ring surface) for each day. Since, in their clinical trials in postpartum women, WHO wanted to use vaginal rings which initially released 5 mg progesterone/day and declines by about 0.5 mg/month under conditions of membrane limited diffusion as the depletion zone grew thicker, the study showed that the rings with a 6 mm core met the criteria. The chemists found that these rings and 4 sterile batches of these rings have highly consistent and reproducible rates in vitro drug delivery. They also compared the vaginal rings with a 6 mm core with rings with at homogeneous dispersion of progesterone throughout the polymer. The homogenous rings 1st released much progesterone then fell quickly from 10->20 mg/day during the 1st week to a gradual release of about 6 mg/day during the end of the 90 days.
ENTRE NOUS. 1991 Dec; (19):15.About 8 million women use the long acting injectable contraceptive depot-medroxy-progesterone acetate (DMPA) and norethisterone enanthate (NET-EN). These progesterone only injectables are not dependent on sexual activity and are easy to administer. Yet they are not always well accepted since they can interfere with menstrual bleeding and often induce amenorrhea. Researchers find that adding estrogen to DMPA and NET-EN treats these irregularities. They must use esters with limited action to protect the endometrium from constant estrogens, however, which requires monthly injections. Thus bleeding occurs once a month just like the normal menstrual cycle. Clinical trials in China of Injectable No. 1 (250 mg 17-alpha-hydroxyprogesterone caproate and 5 mg estradiol valerate) show that it has few side effects and is acceptable. Other trials in China are evaluating monthly injectables with NET-EN or megestrol acetate. Numerous developing countries often as WHO's Special Programme of Research in Human Reproduction for effective, safe, and fully studied monthly injectables. WHO operates under a 2 part strategy: optimum improvement of HPR 102 (50 m NET-EN and 5 mg estradiol valerate) and Cyclofem (25 mg DMPA and 5 mg estradiol cypionate) resulting in a reduction of the dose of at least 1 of the hormones and results of a study of the efficacy and side effects of these 2 injectables. It hopes the study provides the impetus to introduce them into national family planning programs. It demonstrates that they are indeed efficacious, effect fewer changes in the menstrual cycle than the progesterone only injectables, and are well accepted, even though women must go to a clinic every 27-33 days for an injection. Other studies are determining their effects on lipid and glucose metabolism, coagulation, and fibrinolysis. They are also looking at the time needed for ovulation to return. 1 study shows that menstruation returned in all women by the 3rd cycle.
IPPF MEDICAL BULLETIN. 1990 Apr; 24(2):2-4.Breast milk provides infants with their nutritional requirement plus antibodies to combat certain infections. Prolonged breast feeding and concurrent postpartum amenorrhea contribute to natural infertility, but considerable variability occurs among different populations. Further, certain variables exist that contribute greatly to the length of amenorrhea and infertility. They include nutritional status of the mother; length of breast feeding; giving supplements to the infant; frequency and duration of suckling; and geographic, social, and cultural factors. Many studies indicate that the longer a woman breast feeds, the longer she will experience amenorrhea. Anovulation is contingent on the frequency and distribution of nursing episodes day and night and the time of the infant feeds at the breast. Feeding an infant supplementary milk or food also reduces the inhibitory affect of breast feeding on ovarian activity and fertility, especially when supplements are introduced early. Educating mothers about the value of child spacing, breast feeding, maternal nutrition, and contraception should be done during pregnancy and the postpartum period, the times when mothers most often visit health clinics. Mothers should also be informed that it is not possible to anticipate how long they will be infertile while breast feeding, so contraceptive use should be encouraged. If possible, nursing mothers should avoid using hormonal contraceptives because they can interrupt lactation or pose a risk to the infant. IUDs are highly efficacious. If a woman is in a hospital to deliver, postpartum sterilization is another option. Barrier methods are effective, if used regularly, especially during this time of reduced fertility. Since the reoccurrence of menses is unpredictable and the efficacy is not know, nursing mothers should not rely on periodic abstinence.
IPPF MEDICAL BULLETIN. 1987 Apr; 21(2):1-2.Within the past 25 years, steroidal preparations have become available that allow the user contraceptive protection over extended periods of time. There are only 2 injectable preparations presently used at all widely within family planning programs throughout the world: 1) depot medroxyprogesterone acetate (DMPA), and 2) norethisterone enanthate (NET-EN). 1 of the major side effects of progestagen-only contraception has been disruption of normal menstrual bleeding, giving rise to both irregular bleeding and amenorrhea. Several extensive reports on the clinical use of monthly injectables appeared in 1970, but few studies have been reported subsequently. In response to the demand from certain populations to have safe, well-investigated, once-a-month injectable contraceptives with high efficacy and little menstrual bleeding disturbance, the World Health Organization's (WHO) Special Programme of Research in Human Reproduction developed a strategy for the development of a once-a-month contraceptive which involves: 1) the assessment of use-effectiveness and side-effects of HRP102 (NET-EN, 50 mg., plus oestradiol valerate, 5 mg) and Clyloprovera (DMPA, 25 mg., plus estradiol cypionate, 5 mg.); and 2) the optimum improvement of these 2 combined formulas by reduction of the progestagen content. Results from a pharmacokinetic/pharmacodynamic study show that many of the women receiving reduced progestagen dose preparations ovulated during the 3rd treatment month; thus the 2 original preparations, Cycloprovera and HRP102 appear to be the optimal formulations for these combinations of steroids. Plans are being developed to make 1 or both of these available for introduction into certain family planning programs in developing countries early in 1988.
JOURNAL OF STEROID BIOCHEMISTRY. 1979 Jul; 11(1B):461-7.This report succinctly summarizes Phase I and II clinical trials of intravaginal and intracervical delivery systems for fertility control agents (both steroidal and spermicidal) performed at World Health Organization (WHO) Centres internationally. The WHO Special Programme has conceived of and developed a number of vaginal rings (silastic), which are capable of achieving constant release rates of progestogenic steroid for periods of 90 or more continuous days of use. The local administration rules out the possibility of systemic side effects while the constant release is capable of inhibiting sperm migration through the cervical mucus efficacy of these devices incorporating norethisterone, levonorgestrel, and progesterone is in progress. The vaginal ring has also been incorporated with nonoxynol-9, a potent spermicidal agent. Constant daily release of this spermicidal agent also inhibits sperm migration in the cervical mucus, and use-effectiveness studies are underway. An inert intracervical device, designed and manufactured by WHO, is described (figures depict its manufacturer), and though it is suitable for constant release contraception, no such studies have been performed as yet. Numerous tables report particular release rate data for the vaginal rings impregnated with various dosages of progestogen or spermicide.
MEDICAL JOURNAL OF AUSTRALIA. 1979 Oct 20; 2(8):406-7.Drug toxicity testing is required by the U.S. Food and Drug Administration in bitches of beagle dogs for 7 years and in female rhesus monkeys for 10 years at 25-50 times the human dosage. Progesterone, medroxyprogesterone acetate, megesterol acetate, chlormadinone acetate, chloroethynl norethisterone and chloroethynyl norgestrel are some compounds which have induced tumors in beagle dogs. However, the endocrinology of the beagles is unlike that of a woman and binding affinity of synthetic progestogens to breast cytoplasmic progesterone receptors of the beagle and women have striking differences. Some progestogen compounds which do not produce neoplasia in dogs because of too low a dose are most potent in women. Both the WHO and the Committee on Safety of Medicines concluded that progestogen-induced breast tumors in beagles are unhelpful in predicting possible breast cancer in women who use oral contraceptives.
In: Diczfalusy, E., ed. Regulation of human fertility. (Proceedings of the WHO Symposium on Advances in Fertility Regulation, Moscow, USSR, November 16-19, 1976) Copenhagan, Denmark, Scriptor, 1977. p. 21-71This chapter reviews the hormonal changes which occur during the menstrual cycle. During the last days of the preceeding menstrual cycle, plasma levels of luteinizing hormone (LH) and follicle stimulating hormone (FSH) increase. Follicular phase is characterized by gradually increasing estrogens. A few days preceding the LH surge, some little understood changes in estradiol, LH, and 17-hydroxyprogesterone, on one hand, and ACTH, cortisol, and aldosterone, on the other, occur. Evidence indicates that the estradiol peak occurs first, followed by a simultaneous rise and fall in LH and 17-hydroxyprogesterone values. The peak period of LH is about 32-44 hours long, during which time a rise in progesterone levels takes place. Other pituitary and steroid hormones (human chorionic gonadotropin, ACTH, prolactin, testosterine, androstenedione, cortisol, and aldosterone) show elevated levels during the periovulatory period. Ovulation occurs 16-48 hours after LH peak. The period following LH surge is characterized by rapidly increasing levels of progesterone, 17-hydroxyprogesterone, and 20-alpha-dihydroprogesterone, accompanied by moderately increasing estrogen levels to form the typical luteal-phase hormonal pattern. A luteal increase occurs also in levels of several other hormones, ranging from renin activity to angiotension, or from pregninolone to aldosterone. The last part of the luteal phase is characterized by rapidly declining levels of peripheral hormones. The perimenstrual phase around onset of heavy bleeding is characterized by gradually decreasing levels of progesterone, 20-alpha-hydroprogesterone, estradiol, and testosterone, associated with an incipient rise in LH and FSH levels.
Bibliography on human reproduction, family planning and population dynamics: annotated articles and unpublished work in the South-East Asia Region: steroid contraception (including review of current status).
New Delhi, India, World Health Organization, Regional Office for South-East Asia, November 1974. (Special Supplement No. 1) 77 pThis annotated bibliography lists pamphlets, articles, and studies on combined contraceptives; low dose; injectables; long-acting; implants; postcoital; metabolic effects; lactation; long-term effects; biologic effects; metabolism; mode of action; contraception in the male; field studies; use in gynecological disorders; and works in progress on aspects of steroid contraception in centers in the South-East Asia Region. Sample titles are "Inhibition of ovulation for control of conception" and "Action of cyproterone acetate on male reproductive functions." A review of current status of steroid contraception includes a brief history; description of chemical composition; rates of effectiveness; side effects; clinical aspects; and return to fertility. Steroid releasing vaginal rings, IUDs, and intracervical devices are also described.