For the first six months of a relationship, there seems to be a kind of learning curve in a couple's sex life, a new study found. It takes time to get to know what a new partner likes.
The next six months are a relationship's sexual prime: Couples in the study reported the highest satisfaction with their sex lives during this time.
But after that first year, sexual satisfaction slowly declines.
The study, published in the January issue of the Archives of Sexual Behavior, involved about 2,800 heterosexual German adults between 25 and 41, who were queried every year for three years. All of the participants were in relationships.
The results were the same for married and unmarried couples, the researchers found. As expected, people who said that their relationships were high-quality also reported higher sexual satisfaction as a whole.
The researchers didn't find any differences between men's and women's satisfaction. Everyone seemed to peak around six months into the relationship. Figuring out why this trend occurs will require further study.
But there were also some limitations to the researchers' conclusions.
It's impossible to know, for example, if couples' sex lives get better again after three years, or if the results would have been different for gay couples, older couples, or people in other countries. The researchers also relied on people's honest answers to what most would consider a very personal question: "How satisfied are you with your sex life?"
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