Male reproductive disorders

Sharpe, R.M. and Skakkebaek, N.E. (2003). Male reproductive disorders and the role of endocrine disruption Advances in understanding and identification of areas for future research. Pure and Applied Chemistry 75, 2023-2038. 

POSSIBLE REPRODUCTIVE HAZARD OVEREXPOSURE MAY CAUSE (FEMALE, MALE) REPRODUCTIVE DISORDER(S) ... 

SHARPE R M and SKAKKEBAEK N E (1993) Are oestrogens involved in falling sperm counts and disorders of the male reproductive tract Lancet. 341 (8857) 1392-5. 

D. J. Hunter and R. T. Relsey, Pesticide Residues and Breast Cancer The Harvest of a Silent Spring, J. Natl. Cancer Inst. 85 (1995) 598-99 R. El-Bayoumy, Environmental Carcinogens That May be Involved in Human Breast Cancer Etiology, Chem. Res. Toxicol. 5 (1995) 585-90 R. M. Sharpe and N. F. Skakkebaek, Are Oestrogens Involved in Falling Sperm Counts and Disorders of the Male Reproductive Tract Lancet541 (1995) 1592-95. 

Measure of male feminization measuring the distance between the anus and the base of the penis. Measuring the anogenital distance in neonatal humans has been suggested as a noninvasive method to predict neonatal and adult reproductive disorders. 

The number of individuals affected by reproductive disorders is difficult to assess, and few population-based data are available for either men or women. Noticeably absent are data on fecundity and fertility impairments affecting men and only limited information on male-mediated developmental outcomes exists. Population-based data for impaired female fertility are available for select endpoints from the National Surveys of Family Growth (NSFG), which are conducted periodically and most recently in 1995. Data from the NSFG show that 6.2 million women (10.2%) between the ages of 15 and 44 in the United States had impaired fertility in 1995 (Stephen 1996). This number was estimated to increase to 6.3 million women in 2000 (Stephen and Chondra 1998). Other reproductive disorders in females that impact fecundity include endometriosis and polycystic ovarian syndrome (PCOS). The prevalence of endometriosis in women of reproductive age is reported to be 10% (Houston 1984 Olive and Schwartz 1993), and no population-based prevalence data exist for PCOS. 

What of the effects in humans While there is evidence, some of it controversial, that changes have occurred in the reproductive systems of humans in various countries throughout the world over the last fifty years or so, ascribing these changes to particular chemicals, or even to chemicals at all, has been difficult. There has been an increase in testicular cancer as well as breast cancer since 1945, particularly in certain countries. Data from studies of populations in some countries, for example Finland, have indicated that sperm counts and the quality of the sperm in males have declined over the same time period, but by no means aU studies have found this and some have found the reverse. In some places there has been an apparent increase in disorders of the male reproductive system such as... 

The effects of all-trara-retinoic acid on the male reproductive system include gynecomastia, discomfort, potency disorders, reduced fertility, and ejaculatory failure (61). The incidence is reported to be very high, but exact figures do not seem to be available. 

Though EDCs can affect immunological responses, the most studied effects of EDCs are the reproductive and developmental ones. These, which include male and female reproductive disorders, transgenerational effects and developmental effects on the fetus in utero and the developing... 

Many of the endocrine disorders that result in male infertility have been discussed earher in this chapter in the section on male reproductive abnormalities. Testosterone is essential for normal sperm development. Therefore, any disorder that results in hypogonadism (and hence low testosterone concentrations) results in infertility. Among the causes are both hypogonadotropic and hypergonadotropic hypogo-... 

Other endocrine causes of infertility include exogenous androgens, thyroid disorders, adrenal hyperplasia, and testicular failure. Gynecomastia or obesity in the infertile male may signify elevated concentrations of estrogen and possibly testicular feminization syndrome (see earlier section on male reproductive abnormalities). ... 

Baker HWG, Burger HG, DeKretser DM, Hudson B. Relative incidence of etiologic disorders in male infertility. In Santen RJ, Swerdloff RS, eds. Male reproductive dysfunction. New York Marcel Dekker Inc, 1986 341-78. 

Griffin JE, Wilson JD. Disorders of the testes and male reproductive tract. In Williams RH> Foster DW, Kronenberg HM, Larsen PR, Wilson JD, eds. WiUiams textbook of endocrinology. 9th ed. Philadelphia WB Saunders Co, 1998 819-75. 

Though EDCs can effect immunological responses, the most studied effects of EDCs are the reproductive and developmental ones. These, which include male and female reproductive disorders, trans-generational and developmental effects on the fetus in utero, and the developing child will be addressed further in the infertility and development chapters. The reader is referred to the epic work of Theo Colbom, Dianne Dumanoski, and John Peterson Myers, Our Stolen Future [15], to the aforanentioned WHO report [13] and to the literature [16,17] for review discussions of the subject. 

M ale and female hormones play a vital role because they aid in development and maintenance of secondary sex characteristics and are necessary for human reproduction. Although hormones are naturally produced by die body, administration of a male or female hormone may be indicated in the treatment of certain disorders, such as inoperable breast cancer, male hypogonadism, and male or female hormone deficiency. Hormones also are used as contraceptives and for treating the symptoms of menopause... 

In some animals, consumption of a phytoestrogen-rich diet can cause temporary infertility and reproductive system disorders (Irvine, 1999). In humans, lower testosterone levels and a decline in human semen quality over the past century have been luiked to increased exposure to environmental endocrine disrupters (EDCs) (Sharpe and Skakkebaek, 1993). Furthermore, cases of sexual impotence have been reported in males exposed to synthetic estrogens in the pharmaceutical industry (Mattison et al., 1990). If this might be the case, the fetal-prepubertal period and Sertoli cell development would be of critical importance (Sharpe and Skakkebaek, 1993). However, an adverse effect of phytoestrogens on male fertility has yet to be proven. Recent work (Mitchell et al., 2001) addressing this point led to the conclusion that up to 40 mg/day of isoflavones over a two-month period had no effects on gonadotrophin and... 

As would be expected, khat overuse produces symptoms similar to those of other monoamine stimulants, such as cocaine or amphetamine, including signs of sympathetic overarousal. In the extreme this can involve a toxic psychosis. Disorders more frequently associated with chronic khat use in males are headaches, anorexia, insomnia, constipation, and respiratory illnesses (Kennedy et al. 1983). Females report higher incidences of acute gastritis, jaundice, bronchitis and hepatic diseases. Also, cathinone has toxic reproductive effects in humans and experimental animals (Islam et al. 1990). It decreases sperm count and motility, and increases the number of abnormal sperm cells. It also decreases plasma testosterone in rats. 

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