Human development across the lifespan is largely misunderstood or disregarded in today’s world. It does not operate in a vacuum, as is often suggested by the popular media and social elites. It occurs one developmental stage at a time, with the experiences and choices of the prior having a large effect upon the present.
The written criticisms to the Love and Fidelity Network’s Valentine’s Day campaign mentioned here seem to not have taken this into account. Indeed, each inadvertently opposed the tagline that college students’ sexual choices now may make a difference in their future. One critic, in particular, argued that an individual’s sexual choices may have no effect upon his or her future marital happiness. Another was disturbed by the campaign’s reference to “marital dissolution” as something one might “experience.” (For clarification, “experiencing marital dissolution” is an academic term used throughout the scholarly literature and repeated in the posters). The author suggested that the terminology implied “that divorce is something that just happens to you, dictated unavoidably by your past.”
Ironically, the first critic’s criticism and the second’s contradict each other. As was recognized by the first and misunderstood by the second, we were, indeed, suggesting that the possibility of separation and divorce increases with the number of sexual partners, as it does with other risk factors. We acknowledge that “divorce is a decision made by one or both members of a marriage” as was stated by the second critic, while also reinforcing the first premise of the campaign: research demonstrates that divorce is more likely to occur in marriages according to the number of sexual partners of one or both spouses.
The statistical reasoning will be addressed later. The conceptual reasoning, now.
Human development is determined by a (complex) relationship between both continuity and change of individual emotions, thoughts, and behavior as influenced by experiences throughout the life course.
The validity of this broad definition is demonstrated by one of the most complete longitudinal studies of human development ever performed. Developmental psychologists from the University of Minnesota closely tracked 180 children from the prenatal period to adulthood. Remarkably, they not only found predictive significance for salient experiences in each separate age period upon development at the next, but they also found that salient experiences in early childhood were significantly associated with emotions, thoughts, and behavior in early adulthood.
The researchers created a “global adjustment measure” to envelop the developmental success of young adults in three major criteria: adequate progress in the work/training/school area; meaningful relationships with family, friends, and partners; and a functional level of self-awareness.
The researchers used this to measure the cumulative impact of experiences, influences, and choices from each developmental period throughout childhood and adolescence on the young adults’ global adjustment. They found that a composite “early care” variable from ages 6 months to 6 years was moderately correlated at .34 with the global adjustment measure at age 19. For the behavioral sciences, correlational coefficients of .10, .30, and .50 . . . are, by convention, interpreted as small, medium, and large coefficients, respectively.  The correlation’s moderate significance is therefore impressive, given more than a decade of development’s worth of separation in between young adults’ “early care” and their current adjustment.
Even more noteworthy, however, is that the correlation grew stronger the more that other criteria were added: When elementary peer competence was combined with early parental care, the resulting multiple correlation with global adjustment in young adulthood was .45. Furthermore, when the researchers added the amount of stress and social support that the young person experienced in middle adolescence to the other measures, the final multiple correlation was .55.
In other words, the study demonstrated that a young adult’s global adjustment could largely be measured by the sum of his or her experiences leading up to that point. These findings were unparalleled; the developmental “building block” type pattern had not been previously been shown through longitudinal data over such an extended period of time.
The researchers, concluded their findings, in part, by saying,
Because humans participate actively in creating their own experience, what they experience and take forward from any given age frames their later experience to a notable degree.”
They also acknowledged that,
At the same time, salient experiences, especially experiences in important relationships, can have a transforming influence on the person . . . this does not mean that the prior experience is then erased; rather it simply means that there is a new level of complexity of the person . . . In light of transforming experience, prior experience now is part of a different framework for facing the future and interpreting the world. But it is ‘still there,’ and its relative salience depends on many complicated factors, such as particular circumstances, stresses that may arise, particular settings, and the nature of subsequent experience.”
No part of the Minnesota study is directly related to the claims of the Love and Fidelity Network’s intercollegiate poster campaign this past February. Yet the conclusions made by its researchers generally apply. In line with the first conclusion, it is safe to say that choices—including sexual choices—now will make a difference in life (and quite possibly marital) outcomes later. In line with the second conclusion, it is also important to acknowledge that it is certainly possible for an individual to have a number of sexual partners and report the same marital happiness as an individual who had only had sex with his or her spouse, but 1) on average it is less likely and 2) the individual will still be influenced by the prior choice.
The statistical specifics are worth exploring and discussing, but according to this understanding of human development, it is false to claim —as our critics have—that sexual choices are free from developmental consequences in young adults’ futures.
Social science researchers are just beginning to study the effect of the number of sexual partners prior to marriage on a variety of relationship (including marriage) outcomes. There is much to determine, but, when considering a larger perspective of human development, it is not surprising that initial results are demonstrating some (rather than no) effect.
And currently the effect being found is that having multiple sexual partners before marriage inhibits healthy relationship formation and leads to higher rates of divorce. As Jason Carroll, Ph.D. and LFN guest blogger who introduced the theoretical basis for our Valentine’s Day ad campaign via this post, said
In a just-completed study of nearly 2,700 married individuals, my colleagues and I found that spouses who had multiple sexual partners before marriage had lower levels of sexual quality, communication, and relationship stability in their current marriage, even when controlling for a wide range of variables including education, religiosity and relationship length. These findings were similar for husbands and wives. We found no evidence that increasing the number of sexual partners before marriage benefitted later marital outcomes.
 Sroufe, L. A., Egeland, B., Carlson, E. A., & Collins, W. A. (2005). The Development of the Person. The Guilford Press: New York, NY.
 Green, S. B., and Salkind, N. J.(2008). Using SPSS for Windows and Macintosh: Analyzing and Understanding Data. Pearson Prentice Hall: Upper Saddle River, New Jersey.
“For the behavioral sciences, correlational coefficients of .10, .30, and .50 . . . are, by convention, interpreted as small, medium, and large coefficients, respectively.” (p. 259)
 Heaton, T. B. (2002). Factors contributing to the increasing marital stability in the United States. Journal of Family Issues, 23(3), 392-409; Kahn, J.R., & London, K.A. (1991). Premarital sex and the risk of divorce. Journal of Marriage and the Family, 53(4), 845-855; Paik, A. (2011). Adolescent sexuality and the risk of marital dissolution. Journal of Marriage and Family, 73, 472-485; Teachman, J. (2003). Premarital sex, premarital cohabitation, and the risk of subsequent marital dissolution among women. Journal of Marriage and the Family, 65, 444-455.