GONADS by Z Ngwira-unza

Description

This lecture by Z Ngwira provides a detailed examination of gonadal function, focusing on sex steroid hormones, their regulation, and associated disorders. It covers the primary hormones testosterone, oestradiol, and progesterone, explaining their synthesis, binding to Sex Hormone-Binding Globulin (SHBG), and physiological roles in both males and females. The hypothalamic-pituitary-gonadal axis is detailed, highlighting the role of GnRH in stimulating LH and FSH release. In males, the document discusses testicular function, the influence of LH on Leydig cells and FSH on Sertoli cells, and disorders such as hypogonadism, distinguishing between primary (hypergonadotrophic) and secondary (hypogonadotrophic) causes, including conditions like Klinefelter's syndrome and testicular feminization. For females, it outlines ovarian function, the cyclical variation of oestradiol, and disorders like subfertility, amenorrhoea, hirsutism, and virilism. A significant portion is dedicated to the investigation of infertility in both sexes, outlining diagnostic algorithms that incorporate hormone measurements (FSH, LH, progesterone, prolactin, testosterone) and semen analysis. The lecture specifically addresses Polycystic Ovary Syndrome (PCOS) diagnostic criteria and explores hyperprolactinaemia, its causes, and its impact on fertility. This resource is essential for biomedical science and medical students in Zambia, offering a structured approach to understanding endocrine regulation of reproduction, interpreting hormonal assays, and diagnosing common gonadal disorders. Use this comprehensive guide to build clinical competency in reproductive endocrinology and infertility evaluation.