Sex File: How can I tell my boyfriend our sessions go on for too long?

My boyfriend seems quite pleased with himself that he can last for a long time before having an orgasm. However, I don't always want things to go on and on. How can I tell him he is just taking too much time?

By the sound of it, your boyfriend may have taken his sexual cues from porn, where duration is not quite what it seems and is generally enhanced by Viagra and good editing. Unfortunately, the young men watching it don't see what goes on behind the scenes.

If you want to open his eyes, you need to talk to him. And be kind when you do so - most men remember the unspeakable humiliation of premature ejaculation that so often mars their early sexual experiences, but they don't really know how long constitutes too long. And he may have had partners who were delighted with his endurance skills.

Because it generally takes women longer than men to become aroused enough to have an orgasm, being able to sustain an erection and delay ejaculation is often advantageous. The average length of time it takes a woman to get from feeling aroused to having an orgasm is 13 minutes and 25 seconds. That may sound relatively rapid to some people, but not if you compare it with similar research involving men. Figures from two studies that looked at how long it took men to get from arousal to ejaculation found that it took just 5.4 minutes and 6 minutes respectively. In a small social media poll on this topic that I ran recently, the majority of people said that between five and ten minutes was the ideal duration for penetrative sex.

With women tending to take more than twice as long to have an orgasm, being able to last longer should be an advantage. However, most women would probably prefer that this extra time was spent on foreplay. According to the famous sexual researchers Masters and Johnson, sex has four distinct phases: excitement, plateau, orgasm and resolution. If penetrative sex goes on for too long, it's easy to get distracted, and before you know it your excitement has fallen off the plateau and your orgasm is looking unlikely.

If you are losing interest because he is going on too long, there is nothing wrong with asking him to change things up. Variety is, as they say, the spice of life. Tell him that sometimes you'd like sex to be a sprint, not a marathon. The occasional quickie is passionate, spontaneous, fun and, let's not forget, quick. You could also invest in a vibrator because vibratory stimulation was confirmed to be a cheap and convenient treatment for delayed or inhibited orgasm in men in a 2016 study by clinical psychologist Christian J Nelson.

You may find that as your boyfriend gets to know you better, he will relax and stop trying so hard, but if you talk about what you would like and things don't change, you may find that he is not actually able to speed things up. It's worth considering the possibility that the lengthy sessions may not, in fact, be deliberate.

Delayed ejaculation is less common than premature ejaculation, but it does happen. It can be a psychological issue - some men are scared to ejaculate - but it can also be a side effect of antidepressants, drinking too much or taking drugs such as Valium. It can also happen as a result of pudendal neuropathy, damage that is most frequently caused by bike riding, particularly when a bike has a narrow racing saddle. If any of these issues ring a bell with your boyfriend he should talk to a doctor and if necessary get referred to a specialist.

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