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A semen analysis (plural: semen analyses), also called seminogram or spermiogram, evaluates certain characteristics of a male's semen and the sperm contained therein. [ 1 ] [ 2 ] [ 3 ] It is done to help evaluate male fertility , whether for those seeking pregnancy or verifying the success of vasectomy .
Collecting the sperm at home gives a higher sperm concentration, sperm count, and motility, particularly if the sperm is collected via sexual intercourse. [35] If the semen sample is to be collected by masturbation, a specimen from the early stages of the ejaculation should be placed into a clean, unused, sealed collection cup.
In the XY sex-determination system, the female-provided ovum contributes an X chromosome and the male-provided sperm contributes either an X chromosome or a Y chromosome, resulting in female (XX) or male (XY) offspring, respectively. Hormone levels in the male parent affect the sex ratio of sperm in humans. [25]
The 1990s saw significant development in research on male infertility, with reliable results indicating a decline. A 1992 Danish meta-analysis, commonly known as the Carlsen study after its principal author, showed that between 1938 and 1990 a population described as healthy had experienced a significant decrease in sperm count and semen volume.
Males from India had a 30.3% decline in sperm count, 22.9% decline in sperm motility, and a 51% decrease in morphology over a span of a decade. Doctors in India disclosed that the sperm count of a fertile Indian male had decreased by a third over a span of three decades. [ 80 ]
Men aren’t producing as many sperm as they were decades ago. It’s a trend observed around the globe. The pace of decline is accelerating.
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 ...
The male reproductive system contains two main divisions: the testicles where sperm are produced, and the penis where semen is ejaculated through the urethra. In humans, both of these organs are outside the abdominal cavity. Having the testicles outside the abdomen facilitates temperature regulation of the sperm, which require specific ...