There is no uniform clinical standard for how long couples should have intercourse once, mainly according to individual differences, the number of intercourse varies. For young people 20-30 years old, it is normal to have sex 2-3 times a week. If you are over 30 years old to 40 years old, you may have sex once a week. 40-50 years old may have sex once a month, over 50 years old may have sex once a month, over 60 years old, the number of times you have sex will be reduced again. So the age is different, the frequency of sex is not the same, mainly to their own feeling not fatigue is appropriate.