Let’s talk about sex. Are you having enough of it to make you and your spouse happy? Because it turns out frequency might not even matter. A team of researchers from Carnegie Mellon University studied how sex plays a role in our levels of happiness, and found frequency can make or break the mood. The study, published in the Journal of Economic Behavior & Organization, found a busy bed doesn’t mean a happy marriage.

Researchers randomly assigned sex frequencies to 64 healthy married couples between the ages of 35 and 65. Half of the participants were nominated to have twice as much sex as they normally would in a week while the other half maintained the same pace, at their leisure, for three months. Each person was required to complete three different surveys throughout the experiment, with questions asking about a range of things, including health behaviors, happiness levels, frequency of sex, and types of sexual pleasures.

Participants weren’t happier the more they did the deed. In fact, they were less happy. The researchers explained this by saying an increase in sex frequency led to a decline in desire and enjoyment. In other words, it was the experiment's fault.

"Perhaps couples changed the story they told themselves about why they were having sex from an activity voluntarily engaged in to one that was part of a research study,” said the study’s lead author George Loewenstein, from Herbert A. Simon University Professor of Economics and Psychology, according to CBS News. “If we ran the study again, and could afford to do it, we would try to encourage subjects into initiating more sex in ways that put them in a sexy frame of mind, perhaps with babysitting, hotel rooms, or Egyptian sheets, rather than directing them to do so."

Human beings were created to want to have sex because their biology is dictated by the need to procreate, according to the Harvard Business Review. Our instincts drive us to the bedroom, where women find a mate with quality genes and men find a mate healthy enough to bear a child. From an evolutionary standpoint, instincts naturally kick in to increase frequency, and neurohormones such as oxytocin and vasopressin are released, flooding the body with happy feelings that keep us wanting more.

The study may have put a damper on the sexual impetus. All of a sudden, participants weren’t drawn to each other with the primal urge to procreate, but instead to follow through on their assignment by increasing the frequency of intercourse. Sexual satisfaction relies more on the quality of sex than the quantity, as it relies more on those happy hormones flowing without pressure than tallying up notches on a bedpost.

"The desire to have sex decreases much more quickly than the enjoyment of sex once it's been initiated," said Tamar Krishnamurti, a research scientist in CMU's Department of Engineering and Public Policy, who designed the study. “Instead of focusing on increasing sexual frequency to the levels they experienced at the beginning of a relationship, couples may want to work on creating an environment that sparks their desire and makes the sex that they do have even more fun.”

Source: Loewenstein G, Smyth R, Krishnamurti T, and Cheng Z. Sex and happiness. Journal of Economic Behavior & Organization. 2015.