Why Vitality and DNA Matter More Than Just Motility for Sperm Health

Many people believe that their fertility is confirmed by the swimming ability of their sperm. Fertility depends on factors beyond sperm movement, for example, some sperm remain immobile but are able to fertilize an egg and some that appear completely healthy on the surface may contain damaged DNA. This makes conception more difficult and raises the risk of miscarriage. If you and your partner have been struggling to conceive or have had failed IVF cycles, it might not be about how fast your sperm move—but rather how healthy they are.

Sperm Motility vs Vitality

Sperm motility is about movement: the way they swim forward and eventually reach the egg. Poor sperm motility directly reduces the likelihood of natural conception. Vitality, on the other hand, is about life. Some sperm don’t move, but that doesn’t mean they’re dead. Through Intracytoplasmic Sperm Injection (ICSI) treatment, doctors can fertilize an egg by directly injecting a live sperm into it.

Doctors will use special tests to determine sperm viability if semen analysis reveals poor motility. Eosin Y Staining allows experts to distinguish between living and dead sperm. Upon absorption of the dye, dead sperm cells become red, but the living sperm cells remain clear. Alternatively, the test called the Hypo-Osmotic Swelling (HOST) test examines the integrity of sperm membranes. Live sperm respond to special solution exposure by swelling and curling while dead sperm show no change. Assisted reproduction specialists can identify if non-motile sperm have potential use through these tests.

Sperm DNA Damage

Sperm motility and vitality tell us how sperm move and whether they’re alive, but do not indicate if their genetic material is undamaged or not. Sperm DNA fragmentation can lower fertility, increase miscarriage risk, and reduce the chances of IVF success.

DNA damage in sperm can be caused by a variety of factors. First, oxidative stress stands out as a major cause because it emerges from smoking habits combined with unhealthy diet choices and environmental toxin exposure. Second, aging men experience natural decline in sperm quality that leads to more frequent DNA damage. Third, reproductive system infections and inflammation can also damage sperm DNA, as well as varicocele, which causes testicular temperature elevation through scrotal vein swelling. In addition, radiation exposure combined with chemical contact and recurrent fevers may cause sperm DNA fragmentation. Even lifestyle choices like spending too much time in hot tubs or placing a laptop directly on the lap can contribute to the problem.

Specialized testing is necessary to detect sperm DNA damage because it cannot be identified through standard semen analysis. The TUNEL Assay stands out as the most popular test to identify sperm DNA strand breaks. Another method, the Comet Assay allows researchers to determine DNA fragmentation levels in each sperm cell. A higher DNA Fragmentation Index from the Sperm Chromatin Structure Assay (SCSA) indicates decreased potential for fertilization success and embryo development. Doctors might suggest particular treatments or lifestyle adjustments before conception if sperm DNA fragmentation reaches high levels.

How to Improve Sperm Health

The good news? You’re not stuck with poor sperm quality forever. Even if motility is low, vitality isn’t great, or DNA fragmentation is high, there are changes you can make to improve things. A healthier diet and lifestyle can really help. Adding antioxidants like vitamin C, vitamin E, zinc, and CoQ10 to your routine protects sperm from damage caused by stress. Cutting down on smoking and drinking is also huge—both habits can do a lot of harm to sperm. Staying active is a good thing, but avoid activities that expose you to excessive heat, like long bike rides, saunas, or hot tubs, since heat can negatively affect sperm production. In addition, constant stress is another factor that messes with your sperm as it can throw off hormones, impacting their development. Lastly, don't overlook the importance of maintaining a healthy weight, since being overweight can lower sperm quality.

Medical treatments can help men who experience ongoing fertility problems. Doctors use Intracytoplasmic Sperm Injection (ICSI) to select viable sperm from men with good sperm vitality but low motility by directly injecting it into an egg. Some fertility clinics use advanced sperm selection techniques, like Magnetic-Activated Cell Sorting (MACS) or Physiological ICSI (PICSI), to select sperm with the best DNA integrity. If varicocele is a factor, surgery to repair it can lead to improved sperm quality over time. Couples who are currently receiving IVF can benefit from sperm DNA testing because it delivers critical insights which can lead to refined treatment plans and improved fertility results.

Beyond the Swim: What Really Matters for Male Fertility

Fertility isn’t just about sperm movement. If you’ve been trying to conceive without success, it’s worth looking at sperm vitality and DNA integrity to get the full picture.

CARE Fertility delivers various treatment options to maximize your success in fertility. Schedule your consultation now to discuss available choices.

Reference

Gardner, D.K., Weissman, A., Howles, C.M., & Shoham, Z. (Eds.). (2023). Textbook of Assisted Reproductive Techniques: Volume 1: Laboratory Perspectives (6th ed.). CRC Press. https://doi.org/10.1201/9781003268598

. . .

CARE Fertility and Women’s Health is a leading fertility clinic, offering personalized care and advanced reproductive technology to help individuals and couples achieve their dream of parenthood. With state-of-the-art genetic testing, individualized treatment plans, and holistic support, we specialize in complex fertility cases and boast some of the highest success rates in Canada.

Stay Informed!