It also helps to understand that it's normal for erections to come and go during lovemaking -- "It can happen two to five times in a 45-minute sexual session," Mc Carthy says.
And as Laumann's statistics show, only 26% of women report that they always experience orgasm during sex, compared with 75% of men.
Conditions such as thyroid disorders and tumors of the pituitary gland (which controls most hormone production, including sex hormones) can also lower libido.
The class of depression drugs called SSRIs can inhibit desire.
Understanding the various causes is the first step to finding the appropriate resolution.
Impotence, or ED, erectile dysfunction, is not the same as loss of libido, but when you experience one, sooner or later you are likely to feel the other as well.