Human Growth and Development / Unit 13 HGD 1818 short lesson, about 20 seconds
Male Reproductive Change
Captions available
The idea
Male fertility declines gradually from the thirties, with lower semen volume and sperm quality, and testosterone declines throughout adulthood, especially after fifty.
In practice
A significant testosterone decline, called andropause or late-onset hypogonadism, bringing fatigue, low sex drive and muscle loss.
Where people slip
Low testosterone matters clinically only when it comes with symptoms, since individual levels vary greatly.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
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