Hello and Welcome to ‘Ask A Doctor’ service. I have reviewed your query and here is my advice. Intercourse drive is generating in cerebral region and with the age, atrophy of that area may affect the orgasm, but it is very less likely, this is just a possible cause discussed. Besides the first point, it can be due to stress, lack of interest, infection and some environmental factors, alcohol, smoking, diet all these needs to be taken into consideration, because as clear it is not the disease condition that can be tested. Hope I have answered your query, let me know for further assistance.