Frequent Ejaculation May Improve Sperm Quality, New Research Suggests
Encouraging men to have more frequent ejaculations may boost their fertility, according to researchers who found that sperm deteriorates over time although stored in the body. The longer men went without sex, the more their sperm showed signs of DNA damage and oxidative stress, and the more tests rated the sperm as less viable and poorer swimmers.
Challenging Traditional Abstinence Guidelines
The findings have implications for fertility clinics and suggest that doctors may need to reconsider recommending several days of abstinence before sperm collection for testing or treatment. Current World Health Organization (WHO) guidelines recommend men abstain from ejaculating for two to seven days before providing a sperm sample for fertility tests or in vitro fertilization (IVF). However, these guidelines were originally designed to obtain the highest sperm count, not necessarily the best sperm quality.
Study Details and Findings
The research emerged from a meta-analysis combining 115 human studies involving nearly 55,000 men, and 56 studies examining sperm storage in 30 non-human species. Researchers, led by Dr. Krish Sanghvi at the University of Oxford, found that sperm tended to deteriorate while stored in males, regardless of age. “In men, the negative effects we found on sperm DNA damage and oxidative damage were large-ish, so we are confident that this is a biologically meaningful and significant effect,” said Dr. Sanghvi. Proceedings of the Royal Society B.
IVF Trial Supports Shorter Abstinence
While the Oxford study did not find a direct impact of abstinence on fertilization rates in humans, a recent clinical trial involving 453 couples revealed a link. The trial compared pregnancy rates in couples where men abstained for less than two days versus those following the WHO recommendations of two to seven days. The pregnancy rate was 46% with less than 48 hours of abstinence, compared to only 36% with longer abstinence periods.
Finding the Right Balance for Conception
For couples trying to conceive naturally, finding a balance between abstinence duration is key. Abstaining for too long may lead to DNA damage and reduced sperm motility, while abstaining for too little may result in insufficient sperm count or maturity. “For couples, our recommendation would be that longer abstinence is not always a good thing, and that a balance between quantity [and] quality needs to be struck,” Sanghvi explained.
Expert Commentary
Allan Pacey, a professor of andrology at the University of Manchester, noted the growing evidence supporting shorter abstinence times for assisted reproduction like IVF. “This is because with a short abstinence time the sperm are fresher, more motile and have lower levels of DNA damage.” He clarified that the two to seven-day abstinence rule remains important for semen analysis used in diagnosis, allowing for consistent comparisons. However, he emphasized that for actual IVF treatment, “having the freshest, most healthy sperm is probably more important.” Nature
Implications for Assisted Reproductive Technology
Pacey added that advancements in assisted reproductive technology, such as intracytoplasmic sperm injection (ICSI), allow for successful fertilization with lower sperm counts. “We can do IVF treatment with a low number of sperm, and even lower if we do ICSI, so it isn’t as necessary for men to save up their sperm in the way that we once thought.”