No pHallacy: Semen pH Level Matters for Sperm Health
We often think of one particular element of male fertility: sperm. Yes, a man's sperm health is a crucial factor in whether he'll have trouble conceiving. The number and concentration of sperm, the sperm cells' ability to move, their shape and other parameters are all important.
While a sperm connecting with a woman's egg is the engine that initiates conception, the sperm cells themselves are but a small part of the picture. Without a healthy environment to nurture, protect and carry the sperm on its journey, conception isn't likely.
That's why another parameter of a standard male fertility test is the pH level of the man's semen. We'll look at what semen pH is, what the numbers mean and why semen pH is important to men planning to have children.
Much confusion exists about semen. While it is easy to use the words "semen" and "sperm" interchangeably, they are distinct in important ways.
For starters, sperm make up about 2 percent to 5 percent of the volume of a man's ejaculate. Even that tiny fraction of the whole accounts for some 200 million to 500 million sperm per ejaculation—surely making the testes the hardest-working organs in show business by sheer production, if nothing else.
The majority of the man's ejaculatory material—about 65 percent to 75 percent—is made up of fluid produced by the seminal vesicles. Another 25 percent to 30 percent comes from the prostate gland, and less than 1 percent originates in the bulbourethral glands.
'Sperm is something that has to work outside of the body...so their environment is important.'
Semen is rich in fructose to provide sperm with energy. It also contains zinc, vitamin C, potassium, proteins, enzymes, amino acids and other nutrients that sperm need to survive the journey to find the woman's egg.
"It's all about the environment," said Amy Pearlman, M.D., a urologist and the director of the men's health program at the University of Iowa. "Sperm is something that has to work outside of the body. I don't know that there's anything else that is inside of our body that we actually need to have work outside of our body. But that's the case with sperm, so their environment is important."
A key component of that environment is the pH level of the man's semen.
Acidic or basic, and why both are bad
First, a short primer from high school chemistry class: The pH level of any liquid solution refers to where it falls on a scale of acidity versus alkalinity. A liquid's pH determines whether it's more of an acid or more the opposite of an acid: a base.
A perfect neutral balance between acidic and basic (aka alkaline) is a 7. Substances that are more acidic have lower values, and those that are more basic have higher numbers.
For sperm to survive long enough to reach the egg, semen must adopt a protective strategy to keep the little guys alive in the slightly acidic environment of the woman's vagina.
"The pH of semen is slightly more basic than that of the vagina, so it allows the sperm to survive within the vagina," said Neel Parekh, M.D., a men's fertility specialist affiliated with the Cleveland Clinic.
The normal pH range for a man's semen is between 7.2 and 8.0, according to the World Health Organization. Anything outside this range will likely cause trouble when he and a partner try to conceive. Luckily, there are usually just a few possibilities for explaining why a man's semen pH might be off.
"If it gets too high, like a pH above 8—very alkaline—that can be indicative of an infection," Parekh said. "And then if the pH is too acidic, if it's less than a 6.25 typically, that could indicate some sort of obstruction, because most of the fluid is coming from the seminal vesicles."
A possible cause of imbalanced pH
That's the most common issue with semen pH: When it's too low—too far toward the acidic end of the spectrum. As Parekh noted, this can indicate a blockage of the seminal vesicle, preventing it from depositing all of its fluid into the urethra when the man ejaculates.
If a blockage is suspected, urologists may order a transrectal ultrasound of the prostate and the seminal vesicles to confirm the blockage and locate it precisely. If a blockage is confirmed, the man may have to undergo a transurethral resection of the ejaculatory ducts, a procedure that, while invasive, has proved to be effective in repairing this rare condition.
Semen pH is an important component of fertility testing. Along with sperm count, motility (movement) and morphology (shape), semen pH is a vital part of successfully making viable ejaculate.
But it should be noted that there's not much a guy can do on his own to affect semen pH levels. Eat a healthy diet and stay hydrated to promote healthy semen production. Beyond that, semen pH may be largely out of a man's control, despite what the internet states.
"You see the memes about eating a bunch of pineapples changing the taste [of semen] and stuff," Parekh said. "But I don't think anything like that actually changes the acidity of it, the pH."
He added: "I've never read anything about that in the scientific journals, just on Instagram."