The Science of Sex Before Marriage

With a title like this, you might already have some thoughts about what this article will be about. But my goal here is not to make a moral claim as to the “rightness” or “wrongness” or premarital sex. Rather, it’s to simply relay what the scientific data says for those who engage in intercourse outside of marriage. This is for those who may question the benefits of waiting until marriage. Is premarital sex something to avoid just because the Bible says so? Or are there other reasons too?

Firstly, it’s important to appreciate that we are fundamentally hardwired for intimacy. At a basic level, the draw a person feels towards sexual contact is good, regardless if you think of it biologically, psychologically, philosophically, socially, or spiritually. Now, there are certain systems in our brain that move us towards mating (like most animals), and there are additional systems in our brains that wire us to connect with one person, together, for life (unlike most animals). The data demonstrates this in multiple ways.

More happens during sex than just a momentary experience of pleasure. When we are intimate, chemicals are released in our brains that bond us together. Vasopressin is primarily released in male brains and oxytocin primarily in females. However, when we bond then break, bond then break, we damage our capacity to bond strongly to the next person1. It’s similar to how sticky a piece of tape is. The first time you apply it to a surface, it bonds strongly. But if you take it off and apply it to another surface, it’s less adhesive. Soon, it’s barely sticky at all.

Researchers found that those who wait to have sex until marriage, compared to those who don’t, report significantly higher realtionship satisfaction (20%), better communication patterns (12%), less consideration of divorce (22%), and BETTER sexual quality (15%)2. These effects are lessened but still consistent in those who became sexually active later in dating but prior to marriage.

So, the idea that “practice makes perfect” regarding sexual intimacy happens to be backwards, unless it’s all with the same person you’re married to. Likewise, sex while dating can sometimes be thought of as an important way to test if a couple are compatible and whether the relationship can stand the test of time, another assumption that appears disproven by the data. In summary, the longer a dating couple waits to have sex, the better their relationship is after marriage.

Another study3 found that rapid sexual involvement has adverse long-term implications for relationship quality. The researchers’ analyses also suggest that delaying sexual involvement is associated with higher relationship quality across several dimensions.

So why is this? Why might sexual restraint be more beneficial for couples than premarital sex? The evidence appears to point to two reasons, intentional partner selection and sexual symbolism4. Proper partner selection becomes difficult when you receive the strong and immediate chemical (see bonding above), emotional, and relational benefits of sexual intercourse. Those rewards cause a person to overlook and deny deeper, possible incompatibilities in the relationship. Most of us have experienced the “honeymoon” phase of a relationship; we see the other with rose colored glasses, which makes it difficult to see them with an honest perspective. “Early sex creates a sort of counterfeit intimacy that makes two people think they are closer to each other than they really are.”4

Sexual symbolism: anyone who engages in regular sex with the same person will tell you that most of their relationship involves hanging out with friends, rearranging the furniture, going to the movies, cooking dinner, etc. Sure, sex is happening, but statistically occupies very little of your time, even if it’s happening every day. If the only thing that draws you to the person is sex, then you don’t have an actual relationship and certainly not one able to survive the test of time, i.e. real life problems.

Couples can see the value of waiting until marriage when they appreciate that emotional intimacy is the basis for sexual intimacy. When done rightly, sex in a relationship becomes a meaningful symbol of the emotional intimacy shared by a couple. This is difficult to achieve when sex is prioritized at the beginning of a relationship because no time has been spent to build trust, support, safety, and security with one another. Sexual restraint necessitates that couples put a premium on communication and commitment as the basis of their attraction to each other.4 So waiting isn’t so much about what we should avoid, but about what we can pursue. It’s about seeking emotional closeness and trust, as opposed to just abstaining from premarital sex.

So, there is good scientific data to suggest that waiting is better than not. But my goal here is not to shame anyone; I want to help people use every piece of information available to find hope, wellness, and life and bring order to their lives. Regardless of your actions, you are just as valuable and wanted as everyone else. Truly. And there is hope, regardless of how many people you may have been with, of being restored in your ability to form a deep, lasting bond with another person. Not only neurochemically, but also relationally. A friend once told me that his greatest fear was that he would never be worthy of a relationship with the type of person he wanted to marry because he had engaged in premarital sex. That fear ended up being wrong - he’s now happily married with a child.

  1. Hooked, New Science on How Casual Sex Is Affecting Our Children (2008) by Joe S. McIlhnaey, Jr., MD & Freda McKissic Bush, MD.

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