Experimental hypothyroidism during sexual development Testes size and number of spermatozoa in adulthood are determined by postnatal/pubertal proliferation of seminal tubule somatic cell constituents, the Sertoli cells. Cessation of proliferation of Sertoli cells during early development occurs concomitantly with formation of their terminally differentiated population. Transient experimental hy...

Environmental contaminants such as persistent organic pollutants (POPs) are man-made bioaccumulative compounds with long half-lives that are found throughout the world as a result of heavy use in a variety of consumer products during the twentieth century. Wildlife and animal studies have long suggested adverse effects of exposure to these compounds on human reproductive health, which, accordin...

THE DEVELOPMENT OF THE MAMMALIAN REPRODUCTIVE SYSTEM INVOLVES: (1) an indifferent or ambisexual stage, in which both the male (Wolffian) and female (Mullerian) duct systems are present; (2) sexual differentiation, in which the phenotypic sex is expressed by the enhancement of Mullerian structures in the female and Wolffian structures in the male and reciprocal suppression of the opposite duct s...

Globally Harmonized System defines Reproductive Toxicity as “an adverse effects (of chemicals) on sexual function and fertility in adult males and females, as well as developmental toxicity in the offspring.” Several toxicity assessment studies have been performed taking into account the action of toxicants on reproductive activity. Testis is the main organ of male reproductive system and sperm...

Hypospadias is the most common anomaly in the male genital tract with an incidence of 0.8-8.2 per 1000 live male births. Routinely, hypospadias cases are repaired after one year of age, and it is recommended that a child with hypospadias not to be circumcised until hypospadias repair is completed. This study was conducted to determine whether or not circumcision prior to hypospadias repair incr...

<<NOTE TO USER: This module presents several examples of risk factors that affect reproductive health. You can find more detailed information in other modules of the training package that deal with specific risk factors, such as lead, mercury, pesticides, persistent organic pollutants, endocrine disruptors, occupational exposures; or disease outcomes, such as developmental origins of disease, r...

Male adolescents' sexual and reproductive health needs often go unmet in the primary care setting. This report discusses specific issues related to male adolescents' sexual and reproductive health care in the context of primary care, including pubertal and sexual development, sexual behavior, consequences of sexual behavior, and methods of preventing sexually transmitted infections (including H...

Alcohol use affects all three parts of the hypothalamic-pituitary-gonadal (HPG) axis, a system of endocrine glands and hormones involved in male reproduction. Alcohol use is associated with low testosterone and altered levels of additional reproductive hormones. Researchers are investigating several potential mechanisms for alcohol's damage. These mechanisms are related to alcohol metabolism, a...

The reproductive tract of the male Cape porcupine is morphologically and histologically similar to that of New World hystricomorph rodents. Males are reproductively active throughout the year and attained sexual maturity (complete spermatogenesis) at an age of 8-18 months. Testes weight, epididymides weight and seminiferous tubule diameter attained asymptotic values at the age of 23-30 months. ...