Every man should strive to improve his reproductive health, but to do so, it’s useful to know how it functions.
Seminal fluid has a significant role in men’s reproductive health and fertility. But most people aren’t that familiar with all the mechanisms associated with it.
So, scroll down to learn about the production of seminal fluid and why it is crucial.
What is seminal fluid?
Seminal fluid is the fluid emitted from the male reproductive tract. The semen contains sperm cells capable of fertilizing female eggs. It also consists of seminal plasma, i.e., other liquids that maintain the viability of sperm cells.
For centuries, scientists have been exploring seminal fluid to see how it works. The spermatozoa were first observed in ejaculate specimens in the 17th century. Until the discovery of ovum in 1827, the underlying mechanisms of human fertilization weren’t fully understood.
The interest in the development of technologies for seminal fluid analysis increased significantly in the early 1900s.
Scientists designed the standard methodologies for the seminal fluid analysis in the first half of the 20th century. Before the 1930s, the semen analysis was clinically unavailable. This was due to the lack of tools or methods that would test the characteristics of the sperm.
The development of methodologies offered valuable insight into the seminal fluid. They learned a lot about its functions and its relationship with men’s health. Regardless of the available methodologies, the analysis of the seminal fluid is a controversial subject.
For instance, the analysis of the seminal fluid is the gold standard for evaluating sperm production and quality. But, it is a poor predictor of men’s reproductive capacity[i]. We will discuss the role of seminal fluid further in this post.
How is semen produced?
In order to truly understand the semen production process, it’s crucial to know as much as possible about male reproductive health. It would be impossible to take out semen production and leave everything else behind. So we’re going to start from the very beginning.
In the sexually mature man, the testes produce sperm cells. These cells account for only about two to five percent of the total volume of semen. Upon reach puberty, a man will produce millions of sperm cells daily. Each sperm cell is about 0.05 millimeters (0.002 inches) long.
While sperm travels through the male reproductive tract, it is bathed in seminal fluids. These fluids are made and secreted by tubules and glands, which we will discuss below. Once it emerges from man’s testes, the sperm is stored in the epididymis.
The epididymis is a tube that connects the testes and vas deferens. Vas deferens is a duct that transports sperm from the epididymis to the ejaculatory duct. In the epididymis, the secretions of sodium, glyceryl phosphorylcholine, and potassium join the sperm. Then, sperm passes through vas deferens to the ampulla or storage area.
The ampulla secretes fructose to nourish the sperm. It also secretes ergothioneine, a yellowish fluid, to decrease or remove oxygen from chemical compounds. The pre-ejaculatory fluid from seminal vesicles and the prostate dilute the sperm.
That way, they provide a fruitful environment during and after ejaculation. That being said, seminal fluids account for 60% of the total semen volume. These fluids include hormones, prostaglandins, amino acids, fructose, citric acid, potassium, and phosphorus.
In the section above, we’ve learned a lot about the production of semen. As you can see, the seminal fluids, produced in various glands and tubules, serve to dilute the sperm. The seminal fluids work to create a suitable environment for the sperm. That way, they are crucial for healthy fertility.
Let’s take a closer look at essential parts of a male reproductive tract that make seminal fluids.
Cowper’s gland, also known as the bulbourethral gland, is a pea-sized. It is located beneath the prostate at the beginning of the internal part of the penis.
During the process of ejaculation, the Cowper’s glands add fluids to semen. These glands, named after the 17th-century English surgeon William Cowper[ii], are 1cm or 0.4 inch in diameter. They contain a network of small tubules.
The Cowper’s gland excretes clear and thick fluids. They act both as a lubricant and a flushing agent that washes out a man’s urethra before the ejaculation of semen. Fluids from this gland may also serve to make the semen less watery. About 5% of seminal fluid accounts for those secreted by this gland.
The prostate gland is the most well-known gland in a male reproductive tract. This is mainly due to the wide prevalence of prostate cancer and other problems. This walnut-sized gland is located between the bladder and penis.
Prostate adds secretions such as an enzyme acid phosphatase to the sperm during ejaculation, just like the Cowper’s gland. Since it surrounds the urethra, the prostate serves for the passage of both semen and urine. The prostate is slightly bigger than the Cowper’s gland measuring about 4cm or 1.6 inches in its broadest area.
The pre-ejaculate from the prostate is clear, but it can be milky or white, and it’s slightly acidic. That being said, some studies of semen samples showed that prostatic secretions in most healthy men are alkaline[iii]. The prostate fluid contains citric acid and various protein-splitting enzymes. It also includes sodium, zinc, potassium, and calcium. Between 15% and 30% of seminal fluid is produced by the prostate gland.
Seminal vesicles are two saclike glands measuring 5 to 7cm (2 to 2.75 inches) in length and 2 to 3cm in width. They are located within the pelvis. These vesicles secrete their fluid contents in the ejaculatory tract. Fluid from seminal vesicles is thick. It contains fructose, citric acid, proteins, potassium, inorganic phosphorus, and prostaglandins.
When the fluid combines with sperm in the ejaculatory duct, the fructose becomes the primary source of energy for the sperm outside a man’s body. Prostaglandins, on the other hand, support fertilization.
They do so by making the cervix’s mucus lining more “welcoming” for the sperm. Prostaglandins also promote the movement of the sperm toward the ovum. Seminal vesicles produce about 65% to 75% of the seminal human fluid.
What role does seminal fluid play in men’s health?
As mentioned earlier in the post, seminal fluid consists of seminal plasma, which maintains the viability of sperm cells.
That way, seminal fluid plays a significant role in men’s reproductive health. The purpose of seminal plasma is to carry, protect, and nourish spermatozoa after ejaculation up to fertilization.
The spermatozoa are produced in seminiferous tubules. It also acts as a functional modulator of spermatozoa function. The roles and functions of seminal fluid are primarily misunderstood by most people. Seminal fluid contact at conception contributes to the activation of the endometrial gene expression and immune cell changes.
Both are necessary for robust implantation. In other words, seminal fluid influences the quality of the ensuing pregnancy. It also plays a role in the health of the offspring.
A more thorough understanding of seminal fluid and seminal plasma proteins could improve the treatment of male infertility. Even though 50% of couple infertility cases account for men, most treatment options are female-oriented[iv]. Further research on seminal fluid could aid the development of treatment approaches to address male infertility. They could improve men’s reproductive health.
Speaking of the role of seminal fluid in reproductive health and function, it’s useful to mention that the pH of semen affects the motility and capacitation of sperm. In other words, seminal fluid supports pH balance. It contributes to the quantity and movement of sperm.
That’s why changes in pH balance can have a negative effect. Slightly alkaline conditions seem to stimulate human sperm motility and capacitation. But mechanisms of pH affecting the quality of human spermatozoa are not completely elucidated. On the flip side, a slightly acidic pH value of seminal fluid may damage the sperm cell membrane directly. Or it can enhance the active oxygen content, thereby affecting sperm count and motility[v].
The importance of seminal fluid for men’s health is truly immense, as we can already conclude. Seminal fluid is abundant in minerals and provides nutrition to sperm and sperm cells. It’s also responsible for creating a favorable environment that will allow spermatozoa to thrive.
Moreover, seminal fluid could also play a role in the protection of sperm DNA. Seminal fluid abundant in antioxidants and is vital for the protection of spermatozoa from oxidative stress[vi].
For reference, free radicals and oxidative stress harm sperm DNA. That’s why seminal fluid can neutralize those scavengers and protect men’s reproductive health. When talking about reproduction, IgE antibodies to seminal fluid may also contribute to infertility.
One of the major roles of seminal fluid and its plasma is to provide the antimicrobial protection for the spermatozoa in the female reproductive tract. The bactericidal activity of plasma in seminal fluid is the highest after the resolution of the seminal clot. The antibacterial activity of seminal fluid is strictly zinc-dependent both at neutral and low pH[vii].
It’s useful to mention the fact that the presence of some bacteria in human semen can impair sperm quality and lower sperm concentration. As a result, bacterial contamination of seminal fluid can contribute to infertility[viii]. This is yet another reason why taking care of your reproductive health is vital.
While the seminal fluid usually promotes the reproductive function, it also influences prostate health. Studies show that altered seminal parameters in middle-aged men are strongly associated with
- and/or bladder outlet obstruction[ix].
Scientists call for more studies that would evaluate the impact of semen quality and other parameters on urinary tract symptoms and prostate health. The presence of prostate-specific antigen in the fluid may also indicate potentially serious problems such as prostate cancer.
What does your semen say about your health?
Semen speaks a lot about a man’s health, which is why you shouldn’t ignore changes when you see them. Generally speaking, healthy ejaculatory fluid is cloudy white or grey with a jelly-like consistency, which you can easily notice in coitus interruptus instances.
In some men, semen may be yellowish. Normal semen usually has a bleach-like smell due to its pH value. Bear in mind that although it’s normal for semen to have the off-white appearance, pronounced yellow color may indicate the presence of infection like STD. The same applies to men with green semen.
Brownish or red appearance of semen points to the burst of a blood vessel, and it’s not dangerous. You may notice improvements in a day or two. But if the problem persists you may want to consult a doctor.
Some men may notice their orgasm is dry, i.e.; no semen is expelled at all despite strong sexual arousal. In young men, this is normal, but in older men who have undergone some treatments in the prostate area, it could be a sign of retrograde ejaculation. Problems such as seminal fluid hypersensitivity are very rare among men.
The quality and function of seminal fluids and the genital tract depend greatly on your lifestyle. Unhealthy lifestyle choices such as junk food and other foods with little to no nutritional value can impair the pH balance of seminal fluid. Besides an unhealthy diet, other factors that deteriorate seminal fluid quality include a sedentary lifestyle, being overweight or obese, smoking, drinking alcohol.
It’s never too late to enhance the quality of the seminal fluid and support your fertility. Aim to eat a well-balanced diet, exercise regularly, quit smoking, and limit alcohol consumption. A healthy lifestyle will support the pH balance of your seminal fluid and promote the function of all parts of the reproductive tract.
In this post, we focused on seminal fluid and all factors associated with it. Bear in mind that the quality of seminal fluid, and thereby your fertility, depends largely on your lifestyle.
Strive to make healthier choices, especially in the diet, in order to improve your reproductive health more effectively. If changes in semen don’t go away in a few days, feel free to consult your doctor.