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Query: UMLS:C0002453 (amenorrhea)
 6,245 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

On the basis of a series of foreign and Danish investigations, a review is presented of the employment of medroxyprogesterone acetate in depot form (Depo Provera) for contraception. It is emphasized that the method practically invariably involves disturbances in menstruation, most frequently in the form of amenorrhea but accasionally as metrorrhagia or frequent spotting. Patients can usually accept absence of menstruation provided they are informed about this side effect in advance. The effect of the preparation is primarily interpreted as gonadotropin inhibition with cessation of ovulation together with a more peripheral gestagenic effect on the endometrium and cervical mucosa. Thus spermatozoa have difficulty in penetrating the uterine cavity and nidation is prevented. The possibility of a diabetogenic effect is discussed but investigations hitherto have not been able to confirm this. Alterations in blood pressure or coagulation factors have not been demonstrated in any investigations. Investigations of vaginal smears have not revealed significant evidence of an increased incidence of abnormal cells or carcinoma in situ. The method is interpreted as a supplement to the existing forms of contraception and is particularly suitable in cases where combined preparations are contraindicated, where the IUD cannot be employed, or in clients who cannot use oral or other forms of contraception.
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PMID:[Medroxyprogesterone acetate in depot form for contraception]. 54 63

Major developments in birth control vaccines are on the horizon. The human chorionic gonadotropin (hCG) vaccine has entered phase II clinical trials after successful completion of phase I studies at 5 centers in India and 4 centers abroad. It is the most advanced vaccine of its type in the world. The trials are being conducted on women of proven fertility who are sexually active. The available results indicate the efficiency of the vaccine to prevent pregnancy in women at or above titres of 50 ng/ml. A vaccine inducing antibodies against gonadotropin releasing hormone (GnRH) has been approved in India for trials in postpartum women, to determine whether immunization can help prolong lactational amenorrhea. The GnRH vaccine is also in clinical trial in prostate cancer patients at 2 centers in India and in Austria and the Dominican Republic. The follicle stimulating hormone (FSH) vaccine is about to enter phase I clinical trial after completing experimental and toxicological studies. A vaccine against FSH has been developed for human males employing ovine FSH (oFSH) as an immunogen. oFSH adsorbed on alum induces antibodies reactive with human FSH in bonnet monkeys. Immunization leads to oligospermia with resultant impairment of fertilization potential. No reduction in testosterone levels has been reported. Research is in progress to identify antigens on spermatozoa, which could serve as vaccine candidates. PH-20, a protein located on the inner acrosomal membrane of capacitated sperms, has been reported to have 100% contraceptive efficacy in both sexes of guinea pigs in active immunization studies. cDNA probes of PH-20 cross-react with genomic DNAs of mouse, rat, hamster, and human. The sperm antigen, lactate dehydrogenase C4 (LDH-C4), is a glycolytic enzyme. Active immunization with LDH-C4 suppressed fertility in mice, rabbits, and baboons. SP-10, which is a testis-specific human sperm protein, is also a promising candidate.
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PMID:Vaccines for control of fertility. 129 38

Oral contraceptive (OCs) of high efficacy containing estroprogestins (EP) were introduced in the 1960's and since then more than 250 million used them. Their benefits include regular menstrual cycles and protection against genital tumors. Dosage seems to be directly related to risks and benefits, therefore new types of low-dose progestins have been developed. Their mechanism of action is based on hypothalamic- hypophysic control, EP suppress the production of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). Their effects are as follows: the cervical mucus becomes more viscous providing a barrier against spermatozoa, regressive (atrophy) modifications and proliferative alterations of the endometrium, and metrorrhagia induced by estrogens and amenorrhea provoked by progestins. The sequential pill requires administration of estrogens in the 1st phase and estroprogestins in the 2nd phase. They minimize physiological and hormonal effects, but the failure rate is 2-3% per woman year. Combined methods of monophasic, biphasic, and triphasic design are used from the 1st to 5th day of menstruation. They block ovulation with a high degree of efficacy, but the stimulating action of EP on the endometrium produces spotting, premature or late metrorrhagia, and amenorrhea. OCs protect against malignant epithelial tumors of the ovaries. It is estimated that 1700 ovarian carcinomas and 2000 endometrial carcinomas are averted each year by the use of the pill in the US. Endometrial cancer risk is halved by EP. 7 epidemiological studies have found no association between the pill and breast cancer, and the risk of benign mammary lesions is also reduced. Accurate anamnesis is mandatory for prescribing safe OCs including screening for coagulation, hepatic function and glycemia tests, and colposcopic examination. Smoking and the pill as well as age under 16 and over 36 increase risks. Nonetheless, the benefits of EP contraceptives outweigh the risks.
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PMID:[Hormonal contraception using estroprogestins]. 218 66

Progestagen-releasing IUDs were developed to diminish the problems of bleeding and pain with inert and copper-containing IUDs. The intrauterine release of the progestagen causes endometrial atrophy, resulting in impairment of nidation, and interferes with transport of the ovum and the spermatozoa. 2 available types, Progestasert, Biograviplan (Alza Corporation, California; Grunenthal) and Levonorgestrel Nova-T (Leiras Pharmaceuticals, Finland), have been sufficiently tested in multinational trials. Compared with Progestasert, LNG Nova-T showed lower pregnancy rates (Pearl Index 0.30), less risk for ectopic pregnancy, and a longer effective lifetime (7 years). With both IUDs, the amount and duration of menstrual blood loss is decreased. Amenorrhea is a frequently occurring side effect of LNG Nova-T, caused by endometrial atrophy. Intermenstrual blood loss and spotting incidences are not uniformly reduced and are still a frequent reason for removal. Preinsertion counseling may improve the acceptance of these nonhealth threatening side effects. With both IUDs, a decrease in menstrual cramps during periods is perceived and a low incidence of PID is found. Basically, the progestagen-releasing IUD can be recommended to all women who wish an IUD for contraception and to women with contraindications for OCs, especially to those with menorrhagia, anemia, or risk for anemia. (author's)
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PMID:Intrauterine steroid contraceptives. 313 66

Contraception by progestational agents only can be a very effective method when estroprogestational contraception or the IUD are contraindicated. Progestational agents affect the physiochemistry of the cervical mucus, spermatozoa capacitation, the endometrium, and the secretory process of the tubes. Progestins can be administered intramuscularly at a dose of 250 mg every 3 months, or of 450 mg every 6 months; they can also be administered in microdoses of 0.5 mg per os per day. Method of administration can be continuous, every day, discontinuous, from the 5th to the 25th day of the cycle, or mixed, i.e. one agent on a continuous basis every day, and another progestational agent for 5-10 days only. Progestational agents are usually well tolerated; they do, however, cause a series of menstruation disorders, including spotting, amenorrhea, and irregularities of the cycle. Reversibility is very good. Contraindicatoins to this type of contraception are diabetes, obesity, lipid metabolic problems, any cardiovascular pathology, any uterine and breast pathology when it is hormonodependant. Sequential contraception would be better indicated than progestational contraception for premenopausal women.
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PMID:[Isolated progestational contraception. Advantages and disadvantages]. 723 18

During lactational amenorrhea a special type of cervical mucus, similar to that found during the luteal phase, is produced. This mucus, however, is able to support sperm migration. In the study described, the ability of spermatozoa to bind to the human zona pellucida (hZP) after migration through periovulatory and post-partum mucus was studied. Mucus was obtained from exclusively breastfeeding women in amenorrhea at 30, 60, 120 and 180 days post-partum. Periovulatory mucus samples from normally cycling women were used as a control. Flat capillary tubes were filled with BWW culture medium at the top and cervical mucus at the bottom. The tubes were immersed in a semen reservoir and the spermatozoa allowed to migrate through the mucus for 3 h into the culture media. Then the spermatozoa were coincubated with 3-4 hZP for 30 min and the number of bound spermatozoa per zona was counted. Periovulatory cervical mucus had an average Insler score of 14 +/- 0.5 as compared to 4.6 +/- 0.4 for post-partum mucus. Spermatozoa recovered from periovulatory mucus were always able to bind to the hZP in only 68 +/- 7% of the cases. Moreover, spermatozoa recovered from post-partum mucus bound to the ZP in lower numbers than did spermatozoa recovered fro periovulatory mucus (p < 0.03). These results suggest a greater ability of sperm-hZP binding after migration through periovulatory mucus and they also indicate that sperm binding to the ZP is possible even after sperm migration through a low quality mucus.
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PMID:Sperm binding to the human zona pellucida after migration through human cervical mucus. 755 93

Sperm chromosome complements were studied in a man heterozygous for a reciprocal translocation t(2;3)(q24;p26). This man was identified during a family study after his sister was investigated for amenorrhea. A total of 92 spermatozoa were karyotyped after in-vitro penetration of hamster eggs. The frequencies of alternate, adjacent 1, adjacent 2 and 3:1 segregations were 55.4, 36.1, 7.2 and 1.2% respectively. For alternate segregations, the number of normal spermatozoa (n = 25) was not significantly different from the number of spermatozoa carrying a balanced form of the translocation (n = 21), as theoretically expected. The proportion of spermatozoa with an unbalanced form of the translocation was 44.6%. There was no evidence for an interchromosomal effect since the frequencies of numerical and structural abnormalities (unrelated to the translocation) were within the normal range of control donors.
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PMID:Sperm chromosome complements in a man heterozygous for a reciprocal translocation t(2;3)(q24;p26). 798 14

In recent years, there has been a definite renewal of interest in vaginal contraception. Locally applied suppositories and creams contain surfactants such as benzalkonium chloride or phenyl-mercury nitrate which are powerful spermicidal drugs capable of achieving spermatolysis of previously immobilized spermatozoa. They are highly efficient spermicides as indicated by a Pearl's index close to 1.5, provided they are employed exactly as prescribed. Sponge-soaked spermicides remain active for 2 or 3 days which is a good palliative to the short-lived efficacy of other galenical preparations. Locally applied spermicides have the added advantage of possessing bactericidal properties and preventing M.S.T. Vaginal rings inhibit ovulation through a continuous release of progestogen with a strong antigonadotropic action. A number of different rings have been tested with varying degrees of success. When anovulation is actually obtained, it is frequently accompanied by hyperestrogeny, spotting, and amenorrhea. Furthermore, metabolic and in particular lipid disorders induced by progestogens cannot be avoided. (author's modified)
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PMID:[Vaginal contraception in 1982. Realities and perspectives (author's transl)]. 1231 10

The aim was to follow-up gonadal functions in long-term survivors of acute myeloid leukemias (AML) after intensive chemotherapy based on high-doses of cytosine arabinoside (Ara-C) and anthracyclines in the study UHKT-911. Adult patients were treated with at least 3 cycles of chemotherapy including 1-3 courses of Ara-C 10 x 2000 mg/m2/12 h and daunorubicin (DNR) 2 x 45 mg/m2/d. Spermiologic examinations were performed in 7 men by the classic microscopic method and results were evaluated according to the WHOcriteria. Two patients (42- and 47-year-old) after DNR and Ara-C chemotherapy had nearly normal spermiologic findings. The semen of a 49-year-old patient contained normal numbers of spermatozoa with decreased velocity when examined 1 year after chemotherapy but 4 years later exhibited oligoasthenozoospermia. The patient received 4 cycles of Ara-C and DNR plus one cycle with etoposide 350 mg/m2 and mitoxantrone 30 mg/m2. Semen examination of two patients 55- and 59-year-old showed permanent oligoasthenozoospermia with only sporadic progressively motile spermatozoa which might not be compatible with fertilization by sexual intercourse. They received the same chemotherapy including cumulative doses of etoposide 500 mg/m2 and mitoxantrone 36 mg/m2. Semen of two patients after allogeneic bone marrow transplantation exhibited severe oligoasthenozoospermia with no motile spermatozoa. Permanent amenorrhea developed in two women (42- and 46-year-old) during chemotherapy with DNR, Ara-C, etoposide, and mitoxantrone which was not the case in three women (29-40 years old) treated without etoposide and mitoxantrone. Intensive chemotherapy with high-doses of Ara-C and DNR plus one cycle of etoposide and mitoxantrone may cause permanent gonadal dysfunction in middle-aged patients with AML.
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PMID:Chemotherapy for acute myeloid leukemias with cytosine arabinoside, daunorubicin, etoposide, and mitoxantrone may cause permanent oligoasthenozoospermia or amenorrhea in middle-aged patients. 1615 84

This paper reviews the possible participation of melatonin in the process of human reproduction. The results of several studies have shown the clear correlation between melatonin and gonadotropins and/or sexual steroids, which suggest that melatonin may be involved in the sexual maturation, ovulation or menopause. Decreased secretion of melatonin which coexists with increased fertility in the summer is specific for women living on the north hemisphere. Moreover, abnormal levels of melatonin in the blood are associated with several disorders of the hypothalamus-pituitary-gonads axis activity, i.e., precocious or delayed pubertas, hypogonadotrophic or hypergonadotrophic hypogonadism or amenorrhoea. Melatonin binding sites have been demonstrated in the central nervous system (mainly in the pars dystalis of the pituitary and hypothalamic suprachiasmatic nucleus) as well as in the reproductive organs, e.g., human granulosa cells, prostate and spermatozoa. Melatonin can, therefore, influence the gonadal function indirectly--via its effect on gonadotropin-releasing hormone and/or gonadotropins secretion. It may also act directly; several data show that melatonin can be synthesized in gonads.
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PMID:[The influence of melatonin on human reproduction]. 1804 44


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