Research has revealed that sex causes an afterglow which aids in enhancing the bond between the couple and making their relationship stronger.
The glow is caused by the "cuddle hormone" -- oxytocin -- which is stimulated while having sex; researchers are yet to find out the duration of its impact.
This study was carried out by researchers from the Florida State University (FSU), with Andrea Meltzer, a psychological scientist, as the lead author of the study. The research group comprised 214 newly-married couples.
Over a span of two weeks, these couples were asked to make a note of when they had sex. They were also asked to mention their individual satisfaction, and rate the overall experience regarding their partner, their marriage, sex life, and their relationship at that point in time.
They had to rate the above aspects based on a seven-point rating scale, according to which seven was great.
The participants had to also rate their marriage quality at the beginning of the marriage, as well as after four to six months.
When the 14-day study was carried out, the couples admitted to having sex on average four times during that period.
A rise was also observed in their satisfaction levels, as the couples stated that after sex, they were contented and gratified for up to two days or more. All participants had a similar experience, their age or gender played no role in it.
"Our research shows that sexual satisfaction remains elevated 48 hours after sex," Meltzer said in a statement.
"And people with a stronger sexual afterglow -- that is, people who report a higher level of sexual satisfaction 48 hours after sex -- report higher levels of relationship satisfaction several months later," he said further.
But in the follow-up session which took place six months after the reasearch ended, it was found that there was depletion in martial satisfaction among the couples. It was, however, found that those couples who reported having comparatively higher levels of sexual afterglow experienced higher marital satisfaction and lower rates of depletion in this satisfaction.
"The same pattern of effects emerged in the two independent studies, providing robust evidence for sexual afterglow," Meltzer and colleagues note. "Together, the findings suggest that sex is linked with relationship quality over time through the lingering effects of sexual satisfaction," they added.
"This research is important because it joins other research suggesting that sex functions to keep couples pair bonded," Meltzer concluded.