Male Fertility

Probiotics and Male Fertility: Replenishing Good Bacteria May Support Sperm Health


By Chris D. Meletis, N.D.

There are a number of possible solutions that doctors employ when they encounter a patient looking to support fertility. But one of those possible solutions might not be at the top of your doctor’s list. I’m referring to probiotics. Yet, recent research is starting to show that taking a probiotic may be able to support sperm health and serve as a good male fertility supplement.

Probiotics as a Fertility Supplement for Men

A collection of microorganisms known as the microbiota lives in the body. Both good and bad bacteria make up your body’s microbiota. The good bacteria are known as probiotic organisms. For optimal fertility, these probiotics must outnumber the bad bacteria. However, everything from environmental toxins to stress to eating too much sugar and processed food can cause the good bacteria to die and the bad bacteria to take over. Recent research indicates that men with fertility issues such as low sperm count who supplement with probiotics may restore balance by increasing the number of the friendly flora and improving fertility.

For example, 41 infertile men with a condition called oligoasthenoteratospermia—abnormality of sperm density, movement, and shape—were given the probiotic Lactobacillus paracasei together with the prebiotics arabinogalctan and oligo-fructosaccharides plus the amino acid L-glutamine or a placebo.1 In the men receiving the probiotic/prebiotic supplement, measures of sperm count improved. There was an increase in ejaculate volume, sperm concentration, and sperm motility (the movement of sperm). Sperm motility is important because it helps the sperm reach the egg for fertilization. Researchers also observed more sperm with normal form in the men given the probiotic/prebiotic. In addition, testosterone levels improved in the probiotic/prebiotic group compared with the placebo.

In another study, nine men with reduced sperm motility—known as asthenozoospermia—were given L. rhamnosus and Bifidobacterium longum for six weeks.2 Sperm motility improved significantly after the men took the probiotics. DNA fragmentation also was reduced in the men taking the probiotics. In order for sperm to successfully fertilize the egg and for the embryo to develop normally, the integrity of the genetic material in the sperm must be preserved. When sperm DNA fragmentation occurs, abnormal genetic material is found in the sperm. This DNA fragmentation may result in reduced male fertility, failure of in vitro fertilization, and miscarriage. In this study, the probiotics also acted as antioxidants which are known to improve sperm parameters.

Other researchers studied infertile men who had bad bacteria present in the semen.3 They gave the men a combination of an antibiotic with a probiotic, which eliminated the bad bacteria and reduced the rate of recurrence. This led the researchers to conclude, “In a population of infertile men, this may well have a benefit to prevent further impairment of sperm quality and preserve fertility.”

While there isn’t yet data showing a benefit for sperm health in men with no known fertility issues, this research in infertile men is promising, and suggests that all men looking to support fertility may want to consider adding in a probiotic to their daily routine.

Could Probiotics Increase Male Fertility in Overweight Men?

Obesity is known to reduce fertility. The number of infertile men who are obese has increased and couples in which the man is obese are less likely to conceive.4 Being overweight is linked to poor semen quality.5-7 Additionally, in couples where the men are obese, it often takes longer to get pregnant.8 Obese men are typically low in testosterone. This may lead to reduced semen quality, including lower total sperm count (oligozoospermia) and decreased sperm motility.7,9,10

Preclinical studies show probiotics may help support fertility in men who are overweight or obese. For example, a study in obese and normal weight male mice found that giving the mice 1 x 109 CFU of L. rhamnosus BIFOLAC PBO1 improved sperm motility in both the lean and obese mice.8 Testosterone levels also increased.

Why Both of You Might Need a Probiotic to Get Pregnant

Probiotics not only support sperm health and male fertility—women trying to get pregnant can also benefit from these good bacteria. Supporting a healthy vaginal microbiota can lead to improved fertility and lowers the risk of pregnancy complications and preterm delivery.11-14 Furthermore, the mother's vaginal bacteria during a vaginal delivery will have the first big influence in the make up of the baby's gut microbiome. This is why, in my clinical practice, I recommend that both members of a couple trying to conceive take a good probiotic. Choosing a probiotic with a combination of Bifidobacteria and Lactobacillus bacteria is recommended, for example: Bifidobacterium longum, Bifidobacterium bifidum, Lactobacillus rhamnosus, Lactobacillus reuteri, Lactobacillus plantarum, and Lactobacillus acidophilus.

Dr. Chris Meletis

Dr. Chris MeletisDr. Chris Meletis is an educator, international author and lecturer. His personal mission is “Changing World’s Health One Person at a Time.” Dr Meletis has authored 18 books and over 200 national scientific articles in journals including Natural Health, Alternative and Complementary Therapies, Townsend Letter for Doctors and Patients, Life Extension, Natural Pharmacy, and articles.

Dr. Meletis served as Dean of Naturopathic Medicine and Chief Medical Officer for 7 years for the National College of Naturopathic Medicine (now the National University of Natural Medicine). He was awarded the 2003 Physician of the Year by the American Association of Naturopathic Physician of the Year by the American Association of Naturopathic Physicians. He has a deep passion for helping the underprivileged and spearheaded the creation of 16 free natural medicine healthcare clinics in the Portland metropolitan area of Oregon.


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