For new couples, moving too fast or too slow when it comes to getting physical can be a big worry.
Many people wonder when the best time is to start being sexually intimate in a relationship.
The answer is complicated, spanning anywhere from a few dates to a few months after beginning to spend time together.
Valentine's Day is coming soon, signaling a romantic milestone for many couples. But for some new pairs, the worry that your relationship is moving too fast or too slow can become a major concern.
Which got us wondering: When is the best time to start being sexually intimate in a relationship, according to science?
The answer is complicated, spanning anywhere from a few dates to a few months after you start to spending time together.
One of the reasons it's hard to determine the best time in a relationship to have sex is because there hasn't been a lot of research tackling that specific question. Few studies have looked at the health of a relationship as it relates to when couples first had sex, and the research that has been done mostly features specific samples of people — mainly college students or married heterosexual couples.
But here's what we know about commitment and sex
In the early 2000s, Illinois State University communications professor Sandra Metts performed a study to find out whether having an emotional connection — in particular saying "I love you" before having sex — could have a positive impact on a relationship.
Her study of almost 300 college-age men and women found that it did.
In fact, Metts' results suggested that couples who had sex first then said "I love you" after had a negative experience: The introduction of that conversation was often awkward and apologetic.
Metts' study provided a list of classic steps partners should take before they get physical, though it's not a clear indicator of the exact timing to have sex. The list includes getting to know the person, sharing a first kiss, then building up to an expression of commitment.
That emotional connection is one of the key elements of any relationship, psychotherapist Toni Coleman told Business Insider in 2015.
Having a good level of communication and an understanding of where the relationship is headed also helps ensure the experience will be positive, she said.
Barton Goldsmith, a psychotherapist from California, agreed that being on the same page emotionally is helpful for finding the best time to start having sex.
"The most important thing is you both agree not to push," he previously told Business Insider. "Be clear that the person is comfortable."
In other words, it's best to wait at least until you're comfortable with each other and have a better picture of what each person wants in the relationship. But when it comes to how much time that takes, it depends.
Here's what three different researchers have to say:
Option 1: Give it a few weeks
According to Goldsmith, a total of 36 hours spent together is all it takes to be ready. Those hours don't have to be consecutive, he said — it could be a dinner date plus a weekend afternoon spent together, and so on, until the hours add up. For most people, that would probably take a few weeks.
If a couple waits much longer than that, he says, the strong desire to have sex may begin to subside. There's data to back him up — a 2012 study on sexual desire found that after the beginning phase of a relationship, sexual desire can drop.
Option 2: Hold off for a few months
Based on the findings of several studies, Coleman suggests that at least three months into a relationship — or when it's clear the honeymoon phase is over — is the best time to start having sex.
The honeymoon period is the first few months of a new relationship, when feelings of attraction are intense and it seems as if the person you're with can do no wrong.
"You move past that, and your feet are more on the ground," Coleman said, adding that [Metts' study] suggested the couples who "waited until that level fared a lot better than people who had sex on the first, second, or third date."
Goldsmith disagrees, though — he thinks the time after the honeymoon period is too late.
Option 3: Wait until marriage
Some people's religious beliefs dictate that they wait to have sex until after they get married. There isn't much scientific research about how this practice impacts a long-term relationship, however.
In 2010, Dean Busby, the director of the school of family life at Brigham Young University, performed a study that suggested that the longer you delay sex — especially if you wait until marriage — the more stable and satisfying your relationship will be. But Brigham Young University, which funded Busby's research, is owned by The Church of Jesus Christ of Latter-day Saints, which isn't a fan of sexual intimacy outside of marriage.
That said, Busby's study built on a bit of earlier research, including one observational study that looked at data from the National Survey of Family Growth. Those findings suggested that women who had one or more intimate relationships involving sex before marriage were at a higher risk of divorce later down the line. But again, the evidence to support that claim is very limited.
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