Men’s Sperm Performance May Decrease After a Period of Abstinence

Men who abstain from sex for longer periods may see a decline in sperm performance, according to new research.  

A large meta‑analysis published in Proceedings of the Royal Society B: Biological Sciences found that sperm stored in the male body for extended periods can show signs of deterioration, including reduced motility and viability, as well as increased DNA damage and oxidative stress.  

Researchers analyzed data from 115 human studies, covering nearly 55,000 men across 31 countries, alongside findings from 56 studies in animals.  

The goal was to understand how in vivo sperm storage (sperm retained in the body before ejaculation) affects sperm health and reproductive performance.  

In men, longer storage linked to sexual abstinence was associated with higher levels of oxidative stress and sperm DNA damage, along with declines in sperm motility and viability. These traits are important because they influence the sperm’s ability to reach and fertilize an egg.  

The researchers explained that sperm are especially vulnerable to aging because once mature, they can no longer repair DNA damage or easily generate antioxidants. While sperm continue to be produced throughout a man’s life, individual sperm cells begin to age as soon as they are stored, accumulating cellular damage over time.  

Importantly, the study did not find consistent evidence that sperm storage reduced fertilization rates or embryo quality in humans, suggesting that the body—or assisted reproduction techniques—may compensate for some sperm damage.  

“There are some reasons why negative effects on sperm might not necessarily translate to negative effects on fertility,” paper author and biologist Krish Sanghvi told Newsweek. “One possibility is that the poor-quality sperm are just dying more rapidly, so a sperm with more DNA damage or lower motility, due to abstinence, might not even be able to fertilise an egg because it is dead before that.”

However, similar storage effects in animals were linked to reduced fertilization success and embryo quality, highlighting potential long‑term biological consequences. In animals, Sanghvi said they were more confident that sperm storage directly harms fertility.

One key finding was that study design mattered. Research that tracked the same men over time detected stronger negative effects of sperm storage than studies comparing different groups of men, indicating that individual changes may be underestimated in cross‑sectional research.  

The authors stressed that the results should be interpreted carefully. While sperm quality declined with longer storage, the overall effect in men was described as statistically significant but modest. Abstinence is also known to increase sperm quantity, meaning there may be an optimal balance between sperm number and sperm quality.  

The researchers also said the ideal timing depends on the goal. While abstaining for longer can increase sperm count, it may also reduce sperm quality. That means there is often a trade‑off between quantity and performance. “There is no point having many sperm, if the sperm are all immotile when ejaculated, or have damaged DNA,” Sanghvi added.

In situations like IVF, where an entire semen sample is used, a middle ground—neither very short nor very long abstinence—may help balance sperm number and quality. In procedures such as intracytoplasmic sperm injection (ICSI), which rely on selecting a single healthy sperm for injection into an egg, shorter periods of abstinence may be preferable. 

However, the researchers caution that the effects seen in men were relatively small, so these findings should be interpreted carefully and not taken as one‑size‑fits‑all advice.

“If abstinence is for too short a duration, the sperm might not be mature enough, or in sufficient number,” Sanghvi said. “So for couples, our recommendation would be that longer abstinence is not always a good thing, and that a balance between quantity-quality needs to be struck.”

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Reference

Sanghvi, K., Dean, R., Nakagawa, S., Reinhardt, K., Sepil, I., & Vega-Trejo, R. (2026). Sperm storage causes sperm senescence in human and non-human animals. Proceedings of the Royal Society B: Biological Sciences, 293. https://doi.org/10.1098/rspb.2025.3181