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    From Reproductive System

    Female - Ovarian Ligament
    Connects ovary to uterus.
    Female - Ovarian Follicles
    Contain developing oocytes.
    Male - Vas Deferens
    Transports sperm from epididymis to ejaculatory duct.
    Male - Rete Testis
    Network of tubules within the testis.
    Female - Fimbriae
    Finger-like projections that guide egg into uterine tube.
    Female - Cervix
    Lower narrow portion opening into vagina.
    Female - Prepuce of Clitoris
    Skin fold covering clitoris.
    Female - Glans Clitoris
    Exposed portion of clitoris.
    Male - Bulbourethral Glands
    Secrete mucus for lubrication.
    Male - Glans Penis
    Expanded tip of the penis.
    Female - Myometrium
    Thick muscular layer of the uterus.
    Female - Uterus
    Houses and nourishes the developing fetus.
    Male - Tunica Albuginea
    Fibrous covering of the testes.
    Female - Endometrium
    Inner mucosal lining of the uterus.
    Male - Corpus Spongiosum
    Erectile tissue surrounding urethra.
    Male - Epididymis
    Stores and matures sperm.
    Male - Scrotum
    External sac that holds and protects the testes.
    Male - Spermatic Cord
    Contains vas deferens, blood vessels, and nerves.
    Male - Urethra
    Conducts semen and urine to the outside.
    Male - Efferent Ductules
    Connect rete testis to epididymis.
    Female - Infundibulum
    Funnel-shaped end of uterine tube near ovary.
    Female - Perimetrium
    Outer serous covering of the uterus.
    Female - Isthmus of Uterine Tube
    Narrow segment near uterus.
    Female - Fundus of Uterus
    Top portion of uterus above uterine tubes.
    Female - Vestibule of Vagina
    Space between labia minora containing openings.

    Male - Seminal Vesicles

    Reviewed by our medical team

    Produce seminal fluid that nourishes sperm.

    1. Overview

    The seminal vesicles are paired glands located in the male reproductive system that play a key role in the production of seminal fluid, which is a major component of semen. These glands contribute the majority of the fluid that makes up the semen, providing nutrients, alkalinity, and other substances that support sperm function and viability. The seminal vesicles are essential for both the protection and motility of sperm during ejaculation.

    2. Location

    The seminal vesicles are located posterior to the bladder and inferior to the rectum. They are situated on the lateral sides of the prostate, where they lie within the pelvic cavity. Each seminal vesicle is connected to the prostate by the ejaculatory duct, through which semen passes into the urethra during ejaculation. The seminal vesicles are located near the base of the penis, behind the pubic symphysis.

    3. Structure

    The seminal vesicles are small, paired structures that resemble a pair of elongated, coiled tubes. The structure of the seminal vesicles includes:

    • Length and size: Each seminal vesicle is approximately 5 to 7 cm long and 2 cm wide, resembling a sac with a slightly convoluted appearance.

    • Seminal vesicle ducts: The ducts of the seminal vesicles empty into the ejaculatory ducts, which then deliver semen into the prostatic urethra.

    • Glandular epithelium: The inner surface of the seminal vesicles is lined with glandular epithelium, which secretes a thick, viscous fluid that forms a significant portion of semen.

    • Smooth muscle: The seminal vesicles have a muscular layer that helps propel the seminal fluid into the ejaculatory ducts during sexual arousal and ejaculation.

    • Connective tissue: The glands are supported by connective tissue, which anchors them within the pelvic cavity and provides structural integrity.

    4. Function

    The seminal vesicles are primarily responsible for producing and secreting seminal fluid, which contributes to several functions:

    • Semen production: The seminal vesicles produce approximately 60-70% of the total volume of semen. Their secretions are rich in fructose, proteins, enzymes, and prostaglandins.

    • Fructose secretion: One of the key components of seminal fluid is fructose, which provides the primary energy source for sperm motility.

    • Alkaline environment: Seminal fluid is alkaline, which helps neutralize the acidic environment of the female reproductive tract, creating a more favorable environment for sperm survival.

    • Prostaglandins: These hormones in the seminal fluid help to facilitate sperm motility and may influence the female reproductive tract to aid sperm in reaching the egg.

    • Sperm protection: The thick, viscous fluid from the seminal vesicles helps protect sperm from oxidative damage and provides a medium for their transport during ejaculation.

    5. Physiological Role(s)

    The physiological roles of the seminal vesicles are vital for male fertility:

    • Sperm nourishment: The fructose-rich fluid from the seminal vesicles provides energy to sperm, supporting their motility as they travel through the female reproductive tract.

    • Alkaline buffering: The alkaline secretion from the seminal vesicles raises the pH of the semen, neutralizing vaginal acidity and creating a more sperm-friendly environment in the female reproductive tract.

    • Prostaglandins and sperm motility: Prostaglandins secreted by the seminal vesicles play a role in sperm motility, as well as promoting the contraction of the female reproductive tract, which may help sperm reach the egg.

    • Semen composition: The seminal vesicles contribute to the consistency and volume of the semen, helping to protect the sperm during ejaculation and improving their chances of successful fertilization.

    6. Clinical Significance

    The seminal vesicles are involved in several clinical conditions, some of which can affect fertility and sexual health:

    • Seminal vesiculitis: Inflammation of the seminal vesicles, usually due to bacterial infection or sexually transmitted infections (STIs) like chlamydia or gonorrhea. Symptoms may include pelvic pain, painful ejaculation, and blood in the semen.

    • Seminal vesicle cysts: Fluid-filled sacs in the seminal vesicles that may be congenital or acquired. They can cause discomfort, obstruction of semen flow, and affect fertility.

    • Infertility: Dysfunction of the seminal vesicles, such as the inability to produce adequate seminal fluid or obstruction of the ejaculatory ducts, can result in male infertility. Sperm may not be effectively transported, or the seminal fluid may lack the necessary components to support sperm motility and fertilization.

    • Prostate cancer: Cancer that spreads to the seminal vesicles can impact fertility and sexual function. Prostate cancer may involve the seminal vesicles in advanced stages, requiring radiation, surgery, or chemotherapy.

    • Absence or malfunction: Some men may have an absent or underdeveloped seminal vesicle, often associated with genetic conditions like cystic fibrosis, leading to problems with semen production and fertility.

    • Ejaculatory duct obstruction: Obstruction of the ejaculatory ducts, which are formed by the seminal vesicle duct and vas deferens, can lead to painful ejaculation, blood in the semen, or infertility due to impaired sperm transport.

    Proper functioning of the seminal vesicles is essential for male fertility. Early diagnosis and management of conditions affecting the seminal vesicles can help preserve reproductive health and improve the chances of conception.

    Did you know? After fertilization, the egg becomes a zygote and starts dividing, eventually implanting in the uterus.