Instead of the egg waiting patiently to see what sperm makes the successful journey, it turns out it plays a more proactive role through something known as sperm chemotaxis. This is the process where the egg releases chemoattractants, chemical signals that help guide certain sperm toward it! 2020 research indicates that chemoattractants might be influencing how many and which sperm are able to make it to the egg by impacting their motility. Sperm that is deemed the best match will be sent those special chemicals which make certain sperm speed up.
This is an incredible new understanding, but there is a lot working against the sperm before even getting close enough to receive these chemicals in the first place. By understanding what the sperm must overcome, we can better appreciate the importance of supporting sperm health before a couple begins trying to conceive.
The fertility crisis: declining sperm
In men with a healthy sperm count, the average number of sperm per ejaculate ranges from 180 – 400 million. However, it’s been reported that the average sperm count fell from 113 million sperm per milliliter (mL) of semen in 1940 to 66 million per mL in 1990. Also, semen volume went from 3.40 mL to 2.75 mL over this same 50-year period. This means that the average man’s semen contains half the number of sperm as it did 50 years ago, and numbers continue to decline. It’s important to mention that sperm count has not declined at the same rate in less polluted areas of the world during the same period. Also, it’s been observed that sperm motility is declining.
The treacherous journey to the egg
For sperm to make it to the egg successfully, they must accomplish the following:
1. Make it from the testicles through the vas deferens to the urethra and out the head of the penis. Some research shows that up to 30% of men have abnormal semen parameters due to poor sperm quality, making it difficult or impossible to get past this first step.
2. Survive the highly acidic environment of the vagina.
3. Get through cervical mucus.
4. Choose the correct fallopian tube (whichever tube it happens to be in that cycle)
5. Make it all the way through the fallopian tubes to the egg, which is covered in a thick layer of cells. Sperm cells contain enzymes that break down this layer, and many times it requires multiple sperm to allow one through.
Typically, an average of only 200 sperm will successfully make it through all these barriers to the egg. And once those chemoattractants are received by the lucky few, only one can ultimately penetrate and fertilize the egg.
The importance of strong, healthy sperm
As you can see, sperm have a lot working against them. They need to overcome multiple roadblocks, harsh environments, and in the end, only the most genetically compatible will be “chosen” by the egg. Additionally, the average man is working with less sperm than previous generations. Therefore, to create the best chance of having as many healthy sperm as possible, we want to empower men to make research-backed changes at least 3 months before trying to conceive since this is about how long it takes sperm to mature. Starting earlier is even better! The following can help improve sperm quality, count, motility, and protect against genetic damage:
1. Take a high-quality men’s prenatal multivitamin/mineral. Even with the healthiest diet, we live in an environment with many toxic burdens and depleted nutrients in our soil. Antioxidants like vitamins E, C, CoQ10, selenium, zinc, N-Acetyl-L-Cysteine (NAC), and L-carnitine can help support optimal sperm DNA and provide the foundational nutritional requirements needed for robust, healthy sperm.
2. Reduce exposure to environmental toxins/pollutants. Toxins in our environment are a major cause of sperm damage. Taking steps to ensure you are drinking clean water and breathing fresh air are foundational to healthy sperm. Opt for organic foods whenever it’s financially feasible and limit your use of plastics. You also want to avoid things that are more likely to cause damage such as cigarette smoke, vaping, excess alcohol consumption, and drug use. Download our Preconception Guide for more ways you can help reduce your toxic burden.
3. Follow a diet that has been shown to improve sperm quality. Research shows that men who closely follow a Mediterranean diet have higher sperm concentration and total sperm count as well as improved motility and morphology. Learn more about the Mediterranean Diet and what it consists of here.
4. Take steps to address your stress! Chronic and severe stress can interfere with hormones that are needed to produce sperm and help them mature. Whether that means engaging in daily stress reduction practices, making sure you are getting a healthy balance or exercise and rest, or even reaching out for professional help, your sperm and future baby will thank you!
5. Let your sperm chill out! Excessive and prolonged exposure to heat has been linked to a reduction in fertility, known as heat-induced male infertility, due to increased oxidative stress and genetic changes. Avoid things that will expose testicles to too much heat such as a laptop directly on your lap, a phone in your pocket, hot tubs, and tight-fitting underwear and pants.