Premature ejaculation can be an embarrassing problem between the sheets, with many men worrying they have left their partner unsatisfied.
Perhaps reassuringly, an Italian study has revealed just how common the issue is, with nearly a third of men (30%) aged 40 to 79 enduring "shorter than desired ejaculation latency".
Of these men, nearly one in 10 (7%) experience "distress" as a result, which then worsens their "sexual functioning".
Regardless of how distressing they find the issue, premature ejaculation was linked to them "avoiding sexual and non-sexual (petting) stimulation", with the affected also more likely to be in an "impaired" relationship.
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While there is no set definition as to how long sex should last, a previous study of 500 couples from five countries found most men ejaculate 5.5 minutes into intercourse.
The NHS recommends men seek medical attention if around half of their intimate interactions result in what they consider to be premature ejaculation.
The issue can often be resolved at home, with the health service advising men masturbate beforehand, use a thick condom or even "take breaks during sex and think about something boring".
Premature ejaculation is considered to be the most common form of sexual dysfunction in men, with previous estimates putting its prevalence at 3% to 30%.
This "huge variation" came down to an absent "standardised and widely accepted" definition of premature ejaculation, along with "different instruments used to detect its prevalence".
To learn more, scientists from the Maggiore-Bellaria Hospital in Bologna analysed nearly 3,000 men from across Europe.
Of these, 889 (30%) self-reported "rapid ejaculation", with 211 (7%) claiming to be distressed as a result.
More severe levels of distress were linked to "progressive worse sexual functioning", a higher risk of erectile dysfunction and "couple impairment", as published in The Journal of Sexual Medicine.
These men were also more likely to show signs of depression and score poorly on a quality of life assessment.
The results remained the same after the scientists accounted for medication that can cause erectile dysfunction and whether or not the men were in a stable relationship.
Erectile-related distress may be brought on by "personal expectations, fear of not satisfying the partner through intercourse or in other ways [and a] wish to extend personal pleasure during intercourse".
"Embarrassment, guilt, worry, tension and fear of failure, associated with partner's reduced sexual fitness, can eventually lead to marital problems", wrote the scientists.
They pointed out, however, that female-specific issues like a woman's inability to orgasm, or reduced sexual desire or pain during intercourse, "may be the cause, rather than necessarily the consequence", of a man's premature ejaculation.
Premature ejaculation can also be brought on by thyroid or prostate problems, illicit drug use and a man's anxiety about his sexual performance.
Some men may have also been "conditioned": "For example, if a teenager conditions himself to ejaculate quickly to avoid being caught masturbating, it may later be difficult to break the habit," according to the NHS.
A traumatic sexual experience, a strict upbringing when it comes to sex and even a particularly sensitive penis can also affect a man's ejaculation speed.
Some men find having sex with their partner on top allows them to pull away when they are close to ejaculating. Taking a deep breath also "briefly shuts down the ejaculatory reflex".
If relationship problems are to blame, couples therapy can help.
A doctor may also prescribe antidepressants, which can delay ejaculation.
The drug dapoxetine, which has the same mode-of-action as many commonly prescribed antidepressants, was specifically designed to delay ejaculation. It can be used "on demand", with most people being advised to take the drug one to three hours before they plan to have sex.
Viagra – drug name sildenafil – is intended to help men become erect; however, it can also ease premature ejaculation.