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Most of us don’t remember every time we had sex, but we remember the first time. Firsts are often etched hard into memory, and they weigh heavily in the formation of our overall impression; hence the enlarged mark of childhood on our adult lives; hence the importance of the first date in a relationship. We remember our first sexual experience because it was first.
But we also remember it because it was sex. Sex is quite literally a major existential concern, and thus tends to resonate deep and wide in our consciousness. Sex, like money, is never just what it is in itself but serves as a medium through which we experience and manifest--often indirectly and unconsciously--a lot of other things. Sexual behavior is a form of self-expression, through which we figure out and experience our deep values, priorities, fears, and desires. In this way, our sexual conduct reflects us to ourselves, like a mirror. In addition, sexual contact, being contact, is also a social act. It places us in--and represents us to--the world. Because, even if the act itself is private, in the end everyone is likely to know about it, even if they keep it secret. That knowledge will affect our position in the social world.
Our sexual debut (science-speak for first intercourse) is a significant marker of both our self and our social identities.
Now a question: Why did you have sex for the first time when you did? Why not earlier or later? This question is interesting not least because it deals with human decision-making. Life, in a sense, is a sequence of decisions. If we can better understand our internal decision-making processes, we will understand better ourselves, and others, as human beings. We will be better able to anticipate, adjust and repair our interpersonal and social relations.
Simplifying greatly, we can say that psychology presents two views on the issue (beyond the effects of social norms, upon which there is wide agreement). One school of thought sees humans as essentially rational self-enhancing agents, seeking to advance their interests through conscious deliberation and calculation. This view focuses on the role of people’s knowledge, plans, and intentions in their decisions: You heard about that thing called sex and decided to have it; you chose an agreeable partner, a time and a place, and then you had sex.
The second school sees humans as much less organized and aware, less proactive and more reactive. The critical question in this approach is not, “What did you plan to do?” but, “What are you willing to do?” According to this view, the sex happened to you when it happened not because you hatched and executed a plan, but because at some point a guy (or a gal) asked if you were willing and you said, “what the hell, why not; yes.”
The truth is that we incorporate both of these strategies. We can all remember decisions--sexual and otherwise-- we studied and agonized over, and ones we jumped into spontaneously, on the fly. Perhaps surprisingly, we often appear to spend a lot more energy, time, thought and intention on essentially trivial decisions (which phone should I buy?) than on the really crucial decisions (how should I live?). I would argue that really big life decisions--what work or career to pursue, where to live, and with whom--are more likely to happen to us by way of willingness than be made by us in an intentional process of orderly and informed rational deliberation. Buying your new iPhone took awareness, market research, pricing, and planning. Your life partner you met by chance and said, “okay, but it's just coffee, I’m in a rush, the new iPhone just went on sale today.”
Either way, many factors shape the decision to have sex for the first time. How these factors interact is not always clear. The psychological literature has shown, for example, a correlation between the level of adolescents’ intelligence and scholastic achievement and their age of sexual debut. Intelligent, good students wait. Why? Not easy to know. Maybe smart students understand it’s worth it to wait with sex, because of the inherent risks. Alternately, good students may spend too much time in the library to find a partner for sex. Maybe an extraneous factor in the adolescents’ family background--some parental behavior, such as close supervision--affects both classroom and bedroom behaviors.
In this context, it’s also known in the literature that girls who grow up without a father tend to have sex earlier than girls who grew up with a father present. The reasons for this finding are not simple to understand. The father's absence may directly affect the behavior of girls. Or it may alter an aspect of the family’s situation--like financial status--which in turn may cause shifts in girls’ behavior. Perhaps a lack of a father reduces familial supervision. In addition, it is possible that the father’s departure is an expression of his genetic temperament–impulsiveness, say–which he’s bequeathed to his daughter, and her early sexual debut is an expression of this shared temperament. Another interesting theory argues for an essentially evolutionary mechanism. A teenage girl in a stable environment can delay sexual debut, since she and her genes are protected. A teenage girl in a chaotic environment may need to rush to reproduce and pass on her genes, because who knows what will happen to her tomorrow.
Beyond the decision and its determinants, another question looms: in modern society in which considerations of virginity and marriage have largely ceased to be crucial factors in the decision, who cares when sexual activity begins? Can the timing of sexual debut really predict important life outcomes? As we know, many things that appear important at a given moment (what did Justin Bieber do today?) turn out to have been trivial later on in life. On the other hand, seemingly trivial decisions (brushing your teeth every day) often turn out to be crucial for our long-term quality of life.
Now, clearly the timing of sexual debut could have significant implications for a person’s biographical narrative. For example, if you had your first sexual encounter with a loving and considerate partner, the experience can radiate onto your sexual life from then on. Conversely, if your parents caught you red-handed in the middle of the act and went berserk, trauma and shame may continue to attend your future sexual relations. But beyond each of our personal stories, science looks for general laws. In this context, the question arises: Does the timing of sexual debut predict the future? The answer, in general, appears to be yes.
Most studies indicate that sex at a young age (under age 15 in the US) raises the level of risk for future delinquency as well as mental and physical health difficulties (depression, eating disorders, unplanned pregnancy, sexually transmitted diseases).
What about those who choose to wait until the end of the teen years? Recently, Paige Harden, a researcher at the University of Texas at Austin, released an interesting study analyzing a database of longitudinal data on more than 1600 pairs of siblings from adolescence to adulthood (ages 15 to 29). Harden divided the participants into three groups according to their timing of sexual debut: the early group, having sex at age 15 or before, the on-time group who became active between 15-19, and the late group who waited until after the age of 19. Harden tested several quality measures of the participants’ adult lives as linked to their sexual initiation data. Interestingly, Harden’s data showed no differences between the 'early' and ‘on- time’ groups. But those participants who waited with sex at least until the age of twenty were significantly different from the other groups. They earned more money, acquired more education, had fewer partners and reported far fewer problems with their marriages.
What are the reasons for this connection? It’s not easy to know. It is possible that young men and women who chose to delay sex have in common some past influences--a good early attachment relationship with parents, for example. Perhaps those who delayed sex possess some specific temperamental component that makes it easier for them to delay gratification. Ability to delay gratification is generally known as a predictor of health and success in many areas of life. Perhaps late sexual bloomers share a weaker sex drive, and thus are free to decide things coolly and rationally in their youth and in adulthood. Perhaps those who wait for sex are highly selective. Highly selective individuals may not be the first to bite the apple, and they may not bite the most apples, but they are more likely to get a delicious apple.
Alternatively, it could of course be that those who came to sex later benefitted not because of what they did, but rather because of what they were spared--all those awkward, premature sex events that may leave scars. Looking back, how many of us who had sex early would characterize our early sex as both good and empowering?
In Harden’s study, the effect of timing of sexual debut on marriage quality remained significant even after she controlled for the influence of other relevant factors, such as genetic proximity, level of education, religious belief, income, and factors such as the body mass index in adolescence and attractiveness ratings. According to Harden, the decision when to have sex for the first time is a good predictor for the quality of marital relations in the future. (Near future that is. The study did not contain information about middle-aged couples and older.) Obviously this does not mean everyone who waits for sex will marry well (or marry at all: the percentage of married people in the late group was lower than in the others), just as we can’t conclude that early sex necessarily begets an unhappy marriage. Psychological research deals with probabilities, not absolutes. Even the solid link between drunk driving and car accidents, for example, does not mean that every, and only, drunk drivers have accidents.
In sum, much is yet to be discovered about how we decide to begin having sex, as well as the full meaning and implications of that decision. At the end of the day, the science suggests that in addition to looming large in memory, our first sexual experience looms large in our future as well.
