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Semen quality is a measure of male fertility, a measure of the ability of sperm in semen to accomplish fertilization. Semen quality involves both sperm quantity and quality. Semen quality is a major factor in fertility. Cryptorchidism, hypospadias, testicular cancer and poor semen quality make up the syndrome known as testicular dysgenesis ...
A 2001 review on variation in semen quality and fertility by male age concluded that older men had lower semen volume, lower sperm motility, a decreased percent of normal sperm, as well as decreased pregnancy rates, increased time to pregnancy, and increased infertility at a given point in time. [55]
Male infertility can wholly or partially account for 40% of infertility among couples who are trying to have children. [2] It affects approximately 7% of all men. [3] Male infertility is commonly due to deficiencies in the semen, and semen quality is used as a surrogate measure of male fecundity. [4]
Men are fertile continuously, but their sperm quality is affected by their health, frequency of ejaculation, and environmental factors. [25] Fertility declines with age in both sexes. For women, the decline begins around the age of 32, and becomes precipitous at age 37. For men, potency and sperm quality begins to decline around the age of 40.
A 1992 World Health Organization report described normal human semen as having a volume of 2 mL or greater, pH of 7.2 to 8.0, sperm concentration of 20×10 6 spermatozoa/mL or more, sperm count of 40×10 6 spermatozoa per ejaculate or more, and motility of 50% or more with forward progression (categories a and b) of 25% or more with rapid ...
Sperm count declines with age, with men aged 50–80 years producing sperm at an average rate of 75% compared with men aged 20–50 years. However, an even larger difference is seen in how many of the seminiferous tubules in the testes contain mature sperm: In males 20–39 years old, 90% of the seminiferous tubules contain mature sperm.
Alabama lawmakers are advancing legislation that would strictly define who is considered female and male based on their reproductive systems. Opponents said the move could erode the rights of ...
] This may be explained by the fact that sperm banks only accept donors who have good semen quality, and because of the rigorous screening procedures which they adopt, including a typical age limitation on sperm donors, often limiting sperm donors to the ages of 21–39 (see paternal age effect), and genetic and health screening of donors. In ...