I occasionally get letters asking how to increase male fertility so I felt it was time to cover some of the basics. But, first and foremost, let me congratulate you because "it's time to party!" That's right - did you know that the average couple takes 104 times in six months to get pregnant and has sex four times per week!  Okay, you're going to pay the price for the next 18 years, but it's going to be the best half year of your life in the meantime! One in ten women said they literally jumped their man as he walked in the door and another one in ten said they called him home from work for a little love making. Get busy and populate!
Now, in spite of the fact you'd like that to probably last forever, you've got to do your part and maximize your chances for a pregnancy. The drive to have children is incredibly deep for women and you could have a frustrated or even depressed woman on your hands otherwise. And, in spite of what a lot of guys think, often infertility issues have to do with the male not the females. A lot of guys think, "Look! Sperm came out - it can't be my problem." However, it has been recently estimated that the male plays a role in a quarter to a half of all couples with fertility problems. 
So my purpose is to show you males how to give it "your best shot" and optimize the probability of pregnancy from the man's side. Below are the key ways that researchers have found to help you do just that:
CAUTION: Always check with your doctor before taking a supplement. It is his or her job to know the latest research on fertility.
1) Zinc. Low levels of zinc can lead to a reduction in male fertility. Let me quote from one journal article: "Studies have demonstrated that zinc therapy results in significant improvement in sperm quality with increases in sperm density, progressive motility and improved conception and pregnancy outcome." 
2) Saturated Fat. A few recent studies have found that diets high in saturated fat dietary lead to significantly decreased fertility and a tremendous difference in sperm quality.  One of the studies found a dose dependent response to saturated fat in the diet, i.e. the more saturated fat, the less the fertility. In this study, the effect of high levels of saturated fat in the diet was so powerful that the researchers basically speculated that this may explain the decreases in fertility that we have been seeing in many countries around the globe: 
"Our findings are of potentially great public interest, because changes in diet over the past decades may be part of the explanation for the recently reported high frequency of subnormal human sperm counts. A reduction in saturated fat intake may be beneficial for both general and reproductive health."
3) Fruits and Vegetables. Since they help with almost every other physiological function, is it any wonder that fruits and vegetables also improve sperm quality?  And I don't know about you, but I want to be a quality guy. And remember: it's much better to guy organic more than likely - see #4:
TRIVIA: Did you know that your fertility could have been affected by your mother's beef consumption during pregnancy? Read this link on The Importance of the Prenatal Lifestyle.
4) Pesticides. Harvard University recently uncovered evidence that pesticides in fruit and vegetables can actually affect sperm counts and fertility.  Okay, I doubt you're picking yourself up off the floor with that bit of news, but it is nice when science confirms common sense, eh? Basically, they took a group of men and controlled for various known fertility factors and still found an association based on pesticide consumption. Now, admittedly, it involved a lot of assumptions, but it would help explain why sperm counts are so decreased in the last few decades. Again, buy organic if at all possible.
5) Heat. You probably already heard this from the doctor, but heat and sperm do not go together. You might want to consider boxers and, whatever you do, do not set the laptop you know where! Even pants that are too snug can do a number on the little guys. So remember: keep the spring breezes blowing down there.
6) Scrotal Fat. This is an expression for fat in the area of the scrotum (nuts, huevos, balls, etc.). The problem is that fat in this area acts like a nice, warm winter blanket and elevates temperatures of your little swimmers. And as you probably know, this kills and immobilizes sperm. One study found that five out of six infertile males had high scrotal fat.  Yet another study found that lipectomy, a surgical fat-removing procedure, greatly increased sperm count, motility and pregnancy rates.  So what generally causes increased scrotal fat? You guessed it - being overweight.
7) Overweight. If you have a gut around your waste, you should be aware that it is associated with decreased male fertility. Now I have to be careful here: I do not want to make anyone feel guilty about not having children simply because they have some extra pounds. But, on the other hand, I have to tell you the truth and the truth is that a spare tire can lower your odds for pregnancy. Increased BMI (Body Mass Index) in particular has been associated with male infertility. One study found, for example, that men with fertility issues were three times as likely to be overweight with a high BMI (BMI > 30).  Many studies have confirmed this same finding. One study in particular went into great detail and found in 81 infertile men that total sperm count, sperm motility and semen volume were all negatively correlated with various combinations of waist circumference, hip circumference and BMI.  Why are those extra pounds such an issue in pregnancy? Three simple reasons: 1) decreased testosterone, 2) oxidative stress (which can damage sperm DNA amoung other things) and 3) increased temperatures in the scrotum (from fat in the area of the scrotum and from a sedentary lifestyle). Being overweight also can lower follicle-stimulating hormone, FSH, and luteinizing hormone, LH, in overweight men as well, another risk factor.
WARNINGS: 1) If you don't know: Chlamydia is a bacterial STD that is often symptomless. In females, it can potentially result in loss of fertility due to damage to the end of the fallopian tubes and lead to increased likelihood of tubal pregnancies. The solution? Have her get tested yearly with a simple swab or urine test if applicable. 2) Also, read the discussion below for how Viagra and other PDE5 inhibitors may affect fertility! 3) In addition, I would recommend reading this link on Excitotoxins and Your Child: these have the potential to be much more deadly to your childs testosterone and fertility than even pesticides.
8) Stress. We have told you many of the evils associated with Stress and Cortisol: it destroys your brain, your arteries and your testosterone. And you can probably guess where I'm going next: it can also cause fertility issues. This is probably because stress lowers testosterone. In fact, scientists have found out how stress lowers your testosterone: through a tricky little enzyme called 11 HSD-1led 11 HSD-1.  Your body produces most of its testosterone in the "Leydig Cells" and this enzyme keeps cortisol, the primary stress hormone, from pushing down your testosterone. It literally puts the brakes on cortisol from destroying your testosterone. However, in times of stress, there is simply too much coristol versus 11 HSD-1 and this leads to a decrease in your testosterone production. Of course, anything that lowers testosterone is bad for fertility.
In addition, researchers at Berkeley found that cortisol from the adrenals lowers GnRH, thus lowering testosterone and estrogen, and boosts GnIH, which hammers fertility.  So to have a kid you gotta relax! See my links on Stress Management, The Relaxation Response, Secular Meditation and PMR for some good ideas on how to do just that.
9) Excitotoxins. These nasty chemicals, found in many items in your supermarket, can kill your fertility. Be informed and read this section on Excitotoxins. These are also a tremendous risk to your children as well.
10) CoQ10. CoQ10 is more than just an antioxidant: it is also involved in energy production. And, apprently, they give energy to your little swimmers as well. Research shows that in men with male fertility issues, i.e. low male-factor fertility rates, that 60 mg/day of CoQ10 increased sperm motility and fertilization rates significantly.  Another study showed CoQ10 correlated not just with sperm motility but also with sperm count as well. 
11) HRT/Androgel/Testim/Testosterone. CAUTION: Take care with testosterone if you are trying to get your woman pregnant. (You really need to take care if you are trying to get someone else's woman pregnant for completely different reasons.) Supplemental testosterone of any form can lower Leutinizing Hormone (LH) and Follicle Stimulating Hormone (FSH) levels and lead to lower sperm counts and fertility. This requires a urologist or endocrinologist that specializes in this area and is willing to carefully monitor you.
12) Varicoceles. These are basically varicose veins in the testicle area. Some studies have shown that they can decrease fertility and others have shown the opposite. However, WebMD's is unambiguous and states that varicoceles "affect 10% to 15% of men and can interfere with sperm function."  The same article goes on to report a new minimally invasive procedure that uses a small catheter with great success. This procedure was found to significantly improve sperm activity and counts and, in addition, 26% of the couples tested were pregnant six months later. Again, a specialist is recommended if you have this kind of issue. Varicoceles, and the ensuing loss of blood supply to the testicle, can effect all the hormonal output of the affected testicle. One study showed that varicocele surgery boosted testosterone an average of 28% in a test group of 53 infertile males. 
13) Soy. Watch the soy. In a recent study men who had a half serving or more of soy had decreased sperm concentrations to the tune of 41 million less sperm per ml, which sounds like a lot to us. No other sperm parameters were affected, such as motility or quality or semen volume.  But the bottom line is that soy gives you less sperm which could impact fertility rates.
14) L-Arginine. A deficiency in L-Arginine can lead to a low sperm count. Several researchers have used it successfully in his practice to improve fertility and sperm counts (in one case 4 g orally daily).
16) Marijuana or Cannabis. Please tell us you are not a regular cannabis user. Besides problems with fertility, marijuana can effect hormones and erectile strength. Please read this link on How Marijuana Can Destroy Your Hormones, Fertility and Lead to Impotence.
17) Viagra. There is a laboratory study that shows that Viagra negatively impacts sperm. Again, this in the laboratory only and has not been shown in vivo. The researchers found that Viagra actually overstimulated the sperm by affecting something called the "acrosome reaction", which is a critical process whereby sperm releases enzymes to makes its way into the egg for fertilization. This seems to be primarily by ushering more calcium into the cell and also changing the energy levels of the sperm, causing the sperm to be overly active. Again, this is something to consider as many guys take Viagra in order to increase fertility. (Pfizer has gone on record stating that there is no effect on fertility. And if you can't trust a huge pharmaceutical giant, who can you trust?)
However, it should be mentioned that a more recent study on actual human subjects showed that Viagra did actually increase sperm motility by about 30%.  Cialis, on the other hand, decrease sperm motility in the same study by about 25%.
18) Ejaculate. As you know I often point out How Sex is Good for Erectile Dysfunction and Sex is Good for Hormones, but that's not the end of the story: it looks like sex is also good for sperm! Probably because the little guys spend less time in storage, sperm shows higher quality and less DNA damage. (Heat, oxidative damage and other factors can damage sperm as they sit in the male body.) In one recent study males with fertility problems were asked to ejaculate once per day and that signficantly helped reduce DNA damage. 
19) CoQ10. A 2004 study found that CoQ10 improved both sperm counts and motility.  Participants were males aged 25-39 who took a rather hefty 200 mg/day dose for six months.
20) Phthalates. Avoid these bad boys like a plague. These softeners of plastic are linked to lowered sperm quality  and DNA damage . For more information, see this link on Common Chemicals That Lower Testosterone.
21) Chlamydia. Get screened for this STD: a recent study linked it to infertility in both men and women. 
22) Bisphenol-A (BPA). This xenoestrogen is prevalent in plastics and foods and causes a host of health issues, including increased sterility in males. See this link on on Bisphenol-A for more details.
23) Chronic Non-Moderate Alcohol Consumption. Chronic and non-moderate alcohol consumption is strongly associated with lowered testosterone in animal studies. Interestingly enough, lowered testosterone is usually followed by a protective feedback loop where LH (Leutinizing Hormone) and FSH (Follicle Stimulating Hormone) are increased. Unfortunately, in these case alcohol actually lowers all three: testosterone, LH and FSH in unison, which will of course lead to decreased fertility. 
24) Soda. Scientists have found a correlation between coke consumption and lousy sperm counts.  It could be because the Sugar Lowers Testosterone or some other factor that we do not yet understand. At this point, it could also just be the lifestyle of soda drinkers. Regardless, drinking a lot of coke is probably not a good idea if you are trying for children.
25) Panax (Korean) Ginseng. One study on rats showed increased sperm count and motility from Ginseng.  This was verified in a (small) study on male subjects as well. 
26) Avoid Cell Phones? One recent study shows that cell phone usage may lower male fertility levels.  Researchers have not yet isolated an underlying cause, but a likely culprit is alterations in the brain's pituitary output since the men had lowered levels of Luteinizing Hormone.
27) Pomegranate. Fruits and vegetables, in general, improve fertility. So it is not too surprising that one animal study shows the pomegranate increases sperm quality.  (It also can help with erectile function - see my page on Pomegranate Juice and Erectile Benefits.
28) Elevated Prolactin. A very common cause of inferility in men can be elevated prolactin levels.  For some additional information, see this link on Testosterone, Prolactin and Prolactinomas.
29) Tongkat Ali (Eurycoma Longfolia). This herb has been shown in a number of animal studies to greatly improve male fertility. One study on rats found that not only was only plasma testosterone increased but testosterone in the testes as well and sperm counts, motility and morphology were all improved.  Another side benefit of Tongkat Ali is that it also is tied to improved libido in a number of animal studies. 
30) Triglycerides and VLDL. Elevated triglycerides are a risk factor for heart disease and erectile dysfunction, so why not infertility as well, eh? That is what one study found. Not surprisingly, researchers also found VLDL (small dense "bad cholesterol" particles) were also a significant risk factor. Of course, the reason is that these are a sign of the Metabolic Syndrome and Insulin Resistance.  This is a big subject, but elevated triglycerides are generally related to too many refined carbohydrates in the diet. And both VLDL and triglycerides follow around individuals eating high glycemic load carbohydrates like an attack dog, clogging arteries and, apparently, damaging sperm parameters as well.
31) Progesterone. Sperm hyperactivation may not sound like a good thing, but it's actually important in order for the egg to be fertilized. Progresterone is actually one of the major factors responsible for this.  You can get your levels checked at one of these Man Friendly Labs.
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