There are two intriguing twin studies out this month, both published in the April edition of Twin Research and Human Genetics. Although the studies were conducted in different countries (Hungary and Denmark) and each focused on a different subject (one looked at the role of heredity and environment on sexual disorders; the other compared the rate of marriage and divorce between twins and singletons) there were remarkable similarities in their findings. Namely, when it comes to sex, love, and marriage, many twins are late bloomers.
In the Hungarian study, for instance, researchers collected data from 420 same-sex twins to determine the heritability of common sexual problems. I will spare you the titillating details surrounding much of their study and instead focus on their secondary objective—to examine the sexual development of twins. It seems that MZ (or identical twins) are a bit older than DZ (or fraternal twins) when it comes to their first sexual experience (first kiss, getting to “first base,” loss of virginity). Researchers speculate that this delay (about six months on average) is due in part to the intense social relationship that many identical twins share with one another. The desire to experiment sexually just isn’t there at an early age. Since they are content within their own twinship, they don’t feel the need to “look for love in all the wrong places.”
In the other study, Danish researchers compared marriage and divorce rates between 35,975 twins and 91,803 singletons. They controlled for such confounders as marriage age, children within the marriage, education level, age difference between partners, and so forth. They discovered that the overall marriage rate of twins is lower than singletons. In other words, there are a lot of single twins out there in the world. The researchers also found that twins who do marry, do so at a later age than singletons. And finally, the study found that female twins have a significantly lower divorce rate than female singletons. Researchers contend that since twins are masters at negotiation within their own twinship, once they do marry, they know what it takes to make the relationship work. At least female twins do! (These results are very similar to another study done years ago by French psychologist and twin researcher, Rene Zazzo.)
I find these results fascinating as well as very positive. While the authors of both studies suggest that twins are so wrapped up with one another that they have “difficulty” finding and maintaining a relationship that results in marriage, I don’t completely agree. Yes, there are those twins who are so tightly bonded that the thought of breaking their union is just too painful so therefore they remain single, but I believe that they are the exception rather than the rule. (Author Abby Pogrebin writes about such twins in her must-read book on twins, One and the Same.)
Instead, perhaps these findings can be explained by the fact that twins don’t feel the immediate need to go out and seek the love and attention of the opposite sex since they have each other as steadfast companions. If their twin keeps them from succumbing to peer pressure to get a girlfriend or boyfriend before they’re emotionally ready, have sex at a very early age, or elope with someone with whom they not compatible simply to escape a lonely life or an unhappy home, more power to them! With the statistics we hear every day surrounding teenage pregnancy as well as the divorce rate, holding off on both should be seen as a positive. Right?
Still, there is a takeaway lesson from both studies, and that is the need for twins to gain a healthy sense of individuality. No one would want their twins to be so dependent on one another that they become paralyzed with fear at the thought of venturing out alone. As parents of twins, we need to continue our vigilance in helping our children develop a strong sense of self.