The Part of Fertility Most Couples Miss
I want to tell you something I see repeatedly in my practice, and it is something too many couples discover too late in their journey.
Most couples come to me having spent months focused entirely on ovulation tracking, hormone testing, and egg quality. That work matters deeply. But somewhere along the way, sperm health got left out of the conversation. And when we finally look at the male side of the equation, we often find that it has been a significant piece of the picture from the very beginning.
Here is what I need you to understand: a semen analysis that comes back “normal” does not always mean sperm function is truly optimal. Count is one number on one piece of paper. But sperm quality is a much fuller story. Motility tells us how well sperm move. Morphology tells us whether they are shaped correctly. DNA integrity tells us whether the genetic material they carry is intact. Oxidative stress tells us whether the cellular environment is working for or against them.
When I see couples navigating unexplained infertility, recurrent miscarriage, or poor embryo development, male factor is one of the first places I look, even when the semen analysis looked fine.
What Is Actually Driving Poor Sperm Quality
The men I see with poor motility, abnormal morphology, or elevated DNA fragmentation are often surprised when I ask about their sleep, their stress levels, their diet, and what they are exposed to at work or at home. These do not feel like fertility questions. But they are.
In my experience, sperm quality is frequently shaped by issues that men would never connect to fertility on their own:
Poor sleep disrupts hormone production and increases oxidative stress throughout the body, including in the testes.
Chronic stress elevates cortisol, which suppresses testosterone and impairs sperm production over time.
Blood sugar imbalance and insulin resistance create an inflammatory environment that directly affects sperm DNA and mitochondrial function.
Inflammation of any kind, whether systemic or localized, interferes with the delicate cellular processes required for healthy sperm development.
Alcohol and vaping are increasingly underappreciated contributors to sperm DNA damage. Vaping in particular is something I counsel patients on regularly, as the data emerging is concerning.
Toxin exposure through pesticides, plastics, heavy metals, and everyday environmental chemicals disrupts hormonal signaling and sperm production.
Poor diet and nutrient depletion leave sperm without the raw materials they need to develop properly, move efficiently, and protect their DNA.
When I see a man with fertility challenges, I do not want to just name the problem. I want to understand what is driving it. There is almost always something underneath.
One Advantage Men Have in Fertility
Here is something I find genuinely encouraging, and I share this with every male patient I counsel.
Sperm regenerates. The entire sperm production cycle takes roughly 70 to 90 days. That means the lifestyle, nutrition, and supplementation choices a man makes today will be reflected in his sperm quality within a few months. Unlike egg quality, which is shaped over years and is much harder to shift quickly, sperm quality can respond meaningfully to the right targeted interventions in a relatively short window.
That is a real opportunity. And I believe in meeting it with both lifestyle changes and the right nutritional support.
The Nutrients That Matter Most for Sperm Quality
When I counsel patients on nutritional support for sperm health, I focus on nutrients that have scientific backing and address the specific mechanisms most likely to be driving dysfunction.
CoQ10 supports mitochondrial energy production in sperm cells. Sperm are among the most energy-dependent cells in the body, and mitochondrial dysfunction is a major contributor to poor motility.
NAC (N-acetyl cysteine) is a powerful antioxidant precursor that helps reduce oxidative stress, which is one of the most common drivers of sperm DNA damage.
L-carnitine plays a key role in sperm energy metabolism and has been studied for its ability to support motility and overall sperm function.
Zinc is essential for testosterone production, sperm development, and protecting sperm from oxidative damage.
Selenium works alongside other antioxidants to reduce DNA fragmentation and support sperm structural integrity.
Omega-3 fatty acids are incorporated into sperm cell membranes and support both motility and morphology.
Antioxidants broadly protect sperm DNA from the cumulative damage caused by free radicals, which are elevated by stress, inflammation, poor diet, and environmental exposures.
These nutrients work together to support mitochondrial function, improve motility, reduce oxidative stress, and protect the genetic integrity of sperm.
My Approach to Treating Male Factor Fertility
When a patient comes to me with poor motility, abnormal morphology, high DNA fragmentation, recurrent pregnancy loss, or poor embryo development, I do not simply hand him a supplement list and send him home. I want to understand why he is experiencing what he is experiencing.
I look at inflammation markers. I assess insulin sensitivity. I ask about sleep quality and sleep duration. I evaluate toxin exposure and dietary patterns. Nutrient depletion is common and often missed. These are the deeper drivers, and addressing them is what produces lasting change.
This philosophy is also part of the reasoning behind Rejoova Sperm and Rejoova Repair, which I developed specifically for male fertility support. Rejoova Sperm was designed to address sperm count, motility, morphology, and DNA integrity. Rejoova Repair was developed to target oxidative stress, inflammation, and mitochondrial function at a deeper cellular level. These two formulas work in concert because, in real clinical practice, these issues rarely come in isolation.
I want to be clear about something: these formulas are not shortcuts, and they are not replacements for the foundational work. Sleep, movement, whole food nutrition, and reducing toxin exposure form the base of everything. The supplements are designed to address deeper drivers more comprehensively, the ones that lifestyle changes alone do not always reach quickly enough.
Male Fertility Deserves the Same Attention as Egg Quality
At Rejuvenating Fertility Center, I have always believed that fertility is a shared journey, and the science agrees. Male factor contributes to roughly half of all fertility challenges, yet it receives a fraction of the attention, funding, and conversation that egg quality does.
If you or your partner has been told the semen analysis is “normal,” but you are still struggling with unexplained infertility, recurrent miscarriage, or failed IVF cycles, I encourage you to look deeper. A standard semen analysis does not assess DNA fragmentation. It does not evaluate oxidative stress. It does not tell you what is happening at the mitochondrial level inside each sperm cell.
There is often more to the story. And in my experience, when we take the time to find it, we can do something about it.
That is the care I am committed to giving every patient who walks through my door.
Dr. Zaher Merhi is a Co-Founder of Rejoova and the founder of Rejuvenating Fertility Center, with locations in Manhattan, Connecticut, Long Island, Westchester, and Brooklyn. He specializes in less-invasive IVF, ovarian rejuvenation, and personalized fertility care for women of all ages.