In the German Family Panel, researchers followed 2,814 people in relationships across three waves of data collection. On average, sexual satisfaction increased during the first year of a relationship and then gradually declined. Health, quality of intimate communication and conflict style were associated with these patterns. The authors were careful to note that the causes of the changes still require further study.
Another study followed 117 married couples during the first three years of marriage. Average sexual satisfaction also declined, but couples differed noticeably in their trajectories. Even in the data, there is no single mandatory story in which “everything gets worse after a few years.”
A meta-analysis of sexual communication also shows a fairly consistent association between the quality of sexual communication and sexual satisfaction: 93 studies involving almost 38,500 participants were included. That does not prove that communication can solve every incompatibility, but it does help explain why compatibility cannot be reduced to whether preferences matched at the beginning.
Some differences can be incorporated into a relationship. Others become painful or fundamental over time. No amount of “work on your relationship” guarantees that two people will eventually want the same things.
But long-term research also gives us reason to reject the opposite extreme — the idea that sexual compatibility is handed to a couple in finished form and then slowly gets used up.
Sometimes it really does deteriorate, sometimes its form changes. And sometimes, many years later, two people understand each other sexually better because they have learned not to assume they already know the answer to “What do you like now?”