Review Finds Sperm Counts Declining Around the World


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Key Takeaways

  • A new review finds sperm count has decreased more than 50% globally over the past 45 years.
  • The research found sperm counts in South and Central America, Asia, and Africa are declining at similar rates to counts in North America, Europe, and Australia.
  • The review doesn’t pinpoint causes, but experts believe that environmental and lifestyle factors are likely to blame.

A new review, published in Human Reproduction Update, finds sperm counts are declining at a rapid pace around the world. Researchers collected data from 53 countries, and what they found was alarming. Between 1973 and 2018, the average sperm count decreased by 51.6%.

If you find this statistic concerning, you are not alone. “More attention needs to be paid to the situation as it can impact humanity as a whole,” says Kecia Gaither, MD, MPH, double board-certified in obstetrics/gynecology and maternal-fetal medicine. “It's a public health emergency not to be taken lightly.”

You might be wondering what declining sperm counts mean for male reproductive health, why this is happening, and how this may impact overall fertility for couples looking to conceive. Here, we’ll get expert input to help us understand the larger impacts of this study.

Sperm Counts on the Decline

The new research on sperm count was carried out by an international team of doctors. The review is a meta-analysis, meaning researchers combed through already published studies and put the data together to look at trends. The team zeroed in on data about sperm counts from South and Central America, Asia, and Africa, adding this to already collected data about North America, Europe, and Australia.

They found sperm counts in South and Central America, Asia, and Africa matched the declining numbers they had already seen out of North America, Europe, and Australia, which indicates that this declining sperm count is a global phenomenon. “Overall, we’re seeing a significant worldwide decline in sperm counts of over 50% in the past 46 years, a decline that has accelerated in recent years,” Professor Hagai Levine, one of the study researchers, says in a press release.

Christopher Hartman, MD, chief of urology at Long Island Jewish Forest Hills, part of the Northwell Health Hospital network in New York, says the review was well executed. Moreover, he says the results point to a troubling global trend we should all be paying attention to.

“The results demonstrate a relatively sharp decline in both total sperm count and sperm concentration over time, and shows that this is universal throughout the world, as opposed to being limited to specific geographic areas,” Dr. Hartman says.

Why is Sperm Count Dropping?

Although the review is able to demonstrate a sharp decline in sperm count around the world, it doesn’t pinpoint what exactly may be causing it. Matthew Macer, MD, a reproductive endocrinologist at Halo Fertility, says there are several factors that are likely contributing to this decline.

“I believe increased use of chemicals and preservatives in our food is a major cause, in addition to the constant exposure to electromagnetic field radiation through cell phones, laptops, and many other ‘smart’ devices which are constantly in close proximity to our bodies,” he says. As he explains, sperm are among the fastest replicating materials in our bodies, and this makes them especially susceptible to any detrimental environmental exposures.

Dr. Gaither agrees that certain chemicals in our environment, food, and grooming products likely play a role in decreasing sperm count. Phthalates and BPAs (bisphenol-A), which are found in vinyl flooring and personal care products like shampoo and soaps, are particularly problematic, she says. “These chemicals cause endocrine disruption (on the hypothalamic-pituitary-gonadal axis in the brain) in both men and women—ultimately impacting fertility,” Dr. Gaither describes.

Finally, increased rates of certain medical conditions may impact sperm counts, says Dr. Hartman. “Across the world, rates of obesity, diabetes, high blood pressure, and other chronic medical conditions are increasing,” he says. Depression, anxiety, and stress levels are also increasing, he says. “Each of these medical conditions has been shown to negatively impact sperm production and sperm quality,” he explains.

What Does Lower Sperm Count Mean For Male Fertility?

One might assume that lowered sperm counts would negatively impact fertility or a couple’s overall chances of getting pregnant. This is definitely a concern. The somewhat hopeful news is that so far, this study isn’t pointing to a major enough decline in sperm counts for these numbers to drastically reduce the overall chances that couples are able to conceive.

“Although multiple studies have shown a decline in men’s sperm count, there has not been a correlative decline in male infertility,” Dr. Macer says. “This is because as long as a man has over 40-50 million sperm per ml of ejaculate, the pregnancy rates stay steady.”

However, the concern is these trends will escalate and that sperm levels will decrease to an extent that fertility will be widely and negatively impacted. “Once levels begin to drop below this point, which may come sooner than anticipated if this study is accurate, we can expect to see a significant increase in couples taking longer to conceive,” Dr. Macer describes.

Ways To Improve Sperm Count

Thankfully, in many cases of low sperm count, there are simple things you can do to boost your numbers. Sometimes there will be medical reasons for low sperm count and these can be addressed with a fertility specialist like a reproductive endocrinologist or urologist. But when there is no known medical cause, making lifestyle changes can make a real difference, says Dr. Macer.

“The most important thing to do in order to increase the number is to stop doing anything that is well known to cause sperm damage,” Dr. Macer says. This may include stopping smoking, drinking, or using drugs. Make sure to tell your healthcare provider about any medication you are taking because sometimes even prescription drugs, like anti-androgens used for hair loss, can impact sperm count, Dr. Macer says.

You can also go back to basics in terms of maintaining good health habits. “I also recommend making sure to get at least 7 hours of sleep, minimizing stress, and eating a balanced organic diet,” Dr. Macer says. “Improving sleep and stress increases your natural testosterone production as well as your sperm count.”

Consider asking your healthcare provider about supplements that might help. Dr. Macer says supplements that increase antioxidant levels can decrease inflammation in the body and help boost sperm counts. Your provider may also recommend human chorionic gonadotropin (hCG) therapy which can temporarily stimulate your testicles to make more sperm, Dr. Macer describes.

Dr. Gaither emphasizes that making small tweaks to your routine, such as keeping cell phones and laptop computers away from your groin can help. Additionally, warm temperatures can decrease sperm counts, so staying away from hot tubs, and warm baths, and switching from briefs to boxers, can be beneficial.

What This Means For You

Hearing alarming statistics about decreasing sperm counts globally can be stressful. While this information is certainly something we should all take seriously, it’s unlikely that this data will affect you or your family directly at this time. Moreover, if you are having trouble conceiving and a low sperm count is part of the picture, there are many options available for increasing sperm count and boosting your chances of conception. Please touch base with your healthcare provider if you have any further questions about fertility and sperm count.

8 Sources
Verywell Family uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Hagai Levine, Niels Jørgensen, Anderson Martino-Andrade, et al. Temporal trends in sperm count: a systematic review and meta-regression analysis of samples collected globally in the 20th and 21st centuries. Human Reproduction Update. 2022:1-20. doi:10.1093/humupd/dmac035

  2. Hagai Levine, Niels Jørgensen, Anderson Martino-Andrade, et al. Temporal trends in sperm count: a systematic review and meta-regression analysis of samples collected globally in the 20th and 21st centuries. Human Reproduction Update. 2022:1-20.

  3. Kesari KK, Agarwal A, Henkel R. Radiations and male fertility. Reproductive Biology and Endocrinology. 2018;16:118. doi:10.1186/s12958-018-0431-1

  4. Sharma A, Mollier J, Brocklesby RWK, et al. Endocrine-disrupting chemicals and male reproductive health. Reproductive Medicine and Biology. 2020;19(3):243-253. doi:10.1002/rmb2.12326

  5. Balawender K, Orkisz S. The impact of selected modifiable lifestyle factors on male fertility in the modern world. Central European Journal of Urology. 2020;73(4):563-568. doi:10.5173/ceju.2020.1975

  6. Utah Center for Reproductive Medicine. Semen Analysis.

  7. Lee JA, Ramasamy R. Indications for the use of human chorionic gonadotropic hormone for the management of infertility in hypogonadal men. Translational Andrology and Urology. 2018;(3):S348-S352. doi:10.21037/tau.2018.04.11

  8. Hamilton TR, Mendes CM, de Castro LS, et al. Evaluation of Lasting Effects of Heat Stress on Sperm Profile and Oxidative Status of Ram Semen and Epididymal Sperm. Oxidative Medicine and Cellular Longevity. 2016;2016:1687657. doi:10.1155/2016/1687657

By Wendy Wisner
Wendy Wisner is a lactation consultant and writer covering maternal/child health, parenting, general health and wellness, and mental health. She has worked with breastfeeding parents for over a decade, and is a mom to two boys.