Ejaculating more often linked to better sperm quality, study finds

A large-scale review suggests that longer periods without ejaculation may be associated with a drop in sperm quality, challenging common assumptions around sexual abstinence and fertility preparation.

The study, published in Proceedings of the Royal Society B, analysed findings from 115 human studies involving nearly 55,000 men, alongside 56 studies covering 30 animal species, including birds, bees, reptiles and mammals, to examine how sperm storage affects reproductive outcomes.

Researchers found that extended abstinence was linked with reduced sperm motility — the ability of sperm to move effectively — and lower viability, meaning a higher proportion of non-living cells. The analysis also associated longer storage periods with increased DNA damage in sperm cells.

Across animal models, embryos produced using older sperm showed lower survival rates. This effect was observed whether sperm was stored within males before ejaculation or retained in females before fertilisation.

The study suggests that biological changes during storage may explain the decline, as sperm appears to lose functional integrity over time compared with newly produced cells.

Findings also showed that while sperm quality decreases after mating in females, the process is slower due to protective compounds within the female reproductive tract that help preserve sperm for longer periods.

In humans, sperm typically survives for several days inside the female reproductive system. Some species, including queen ants, bees and female bats, can store sperm for months or years before fertilisation.

The authors say the results could influence approaches to fertility treatment, including assisted reproduction procedures. They note that using freshly ejaculated sperm may improve outcomes in some cases.

Current World Health Organization guidance recommends abstaining from ejaculation for two to seven days before semen analysis or procedures such as in vitro fertilisation. However, the researchers suggest that shorter abstinence periods may better reflect optimal sperm quality.

Lead researcher Krish Sanghvi said prolonged abstinence may not always be beneficial when fertility outcomes are the priority.

He added that sperm quality plays a decisive role alongside quantity, particularly in procedures like IVF, where both factors influence success rates.