Erectile dysfunction is a far more common problem than many people may think, with as many as seven to eight per cent of men aged 20 to 40 finding it an issue. As men get older, this statistic grows, with Dr John Tomlinson of The Sexual Advice Association advising the figure may be as high as 11 per cent of those aged 40 to 50, and 40 per cent of men over the age of 60.
"A variety of things cause it," he says. "Some psychological and some physical. Psychological issues tend to affect younger men, such as first night nerves and so on. Often, these problems don’t persist. But there can be more serious psychological problems about sex that need the help of a psychosexual therapist."
While sexual intercourse is of course a physical undertaking, there are a huge amount of psychological and emotional components to things going smoothly in the bedroom - nerves, pressure to perform, body hang-ups and so on.
"Worries about work, money, your relationship, family and even [the state of] worrying about not getting an erection can all be factors," the expert explains. Depression and hormonal imbalances causing other psychological issues can also play a role in hampering a man's ability to get - and keep - an erection.
As Dr Tomlinson points out, the thing about psychological causes is these can be far easier to deal with than some of the physical problems. If you are dealing with depression or anxiety - perhaps relationship problems, a lack of confidence in the bedroom or a history of sexual abuse - speaking to a therapist about these problems may help you to move away from these issues and put them in the past.
The very act of getting an erection is of course a biological process. When a man becomes aroused, the brain sends signals to nerves in his penis, which increases blood flow to the area. This in turn causes the tissue to expand and harden. If this series of actions doesn't happen in the way that it is supposed to, this can cause erectile dysfunction.
There are four main categories of physical condition of this sort: vasculogenic (affecting the flow of blood to the penis), neurogenic (affecting the nervous system - the brain, spinal cord and nerves), hormonal and anatomical (pertaining to the actual structure of the penis itself).
Vasculogenic factors include cardiovascular disease, high blood pressure (hypertension) and diabetes, the latter of which could also be considered to be neurogenic as it can have an impact on the nerve endings in the penis. Multiple sclerosis, Parkinson's disease, a spinal injury or disorder of sorts and stroke incidence would all be considered neurogenic conditions.
Hypogonadism - when not enough testosterone is produced - can also be a factor, as can an overactive or underactive thyroid or Cushing's syndrome (affecting the production of the hormone cortisol), which all fall into the hormonal category.
Finally, conditions affecting the physical anatomical structure of penis - such as Peyronie's disease - may also mean that a man is unable to get and keep the erection he desires.
Taking certain medication - such as diuretics, antihypertensives, antipsychotics, corticosteroids or antihistamines - may also present unfavourable side effects in the down-there area, so if you suspect that this may be a cause for your problem, then it is recommended to speak to your GP about this.
Meanwhile, some physical causes can be completely self-inflicted - such as drinking too much alcohol or using recreational drugs - and so if you engage in such behaviours, it would be advisable to stop consuming these, for this reason and many others besides.