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How do the seminal vesicles contribute to semen?
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human reproductive system
Organs and structures of the male and female reproductive systems.
The seminal vesicles are two elongated, saclike glands that play a critical role in the composition of semen. They contribute approximately 60 percent of the total volume of fluid emitted during ejaculation.12
This secretion is a thick fluid containing several essential components that support sperm health and fertilization:
- Energy Source: It provides fructose, which serves as the primary fuel for sperm motility outside the male body.12
- Fertilization Support: The fluid contains prostaglandins, which are believed to aid fertilization by inducing peristaltic contractions in the female reproductive tract and making the cervical mucus more receptive to sperm.1
- Chemical Composition: It also includes proteins, citric acid, inorganic phosphorus, and potassium, which help create a suitable environment for sperm.12
During ejaculation, the muscular walls of the seminal vesicles contract to empty these contents into the ejaculatory ducts, where they mix with sperm arriving from the vas deferens.12