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The phrase "seven-year itch" comes up periodically in casual conversation: Observers try to make sense of other couples' relationship troubles, people try to explain their own relationship restlessness, or partners might use it as an excuse for their wandering eye. But how good of an excuse is it?
Does the seven-year mark put couples' relationships at risk?
The basic idea behind the "seven-year itch" is that romantic partners experience turbulence and a potential point-of-reckoning around seven years together. Viewed as a critical juncture, the seven-year itch is defined as a time when couples re-evaluate: They either realize that their relationship isn't working, or they feel deeply satisfied and committed to their relationship.
Is the seven-year itch a real thing?
From a developmental perspective on relationships, the seven-year itch has a commonsense appeal. Initially, newly-married couples experience a well-documented relationship high, often referred to as a honeymoon phase. This honeymoon phase is characterized by high relationship satisfaction (Kurdek, 1998). Couples are basking in mutual infatuation, joy (or relief) at meeting the social expectation of marriage, and/or rosy illusions of what marriage and their life together with their partner might be like. It's a wonderful feeling.
And then... there's a transition. Newly-married couples, particularly those who have not cohabited previously, must negotiate chores and responsibilities, coordinate their work-life balance, and in other ways merge their lives. This process is not always smooth. While not all couples move through their first few years in the same way (Lavner & Bradbury, 2010), most experience at least some declines in satisfaction as their relationship continues.
If declines in satisfaction reach a height at approximately seven years, maybe that would explain the common phrase, seven-year itch. A peak in instability, however, appears to come earlier.
Or is it four years?
Although people talk about seven years, divorce rates have historically peaked at around four years (Fisher, 1989). Biological anthropologist Helen Fisher argues that this four-year peak makes sense from an evolutionary perspective.
In the course of human evolution, women who changed partners after four years together (enough time to co-parent through the early hard years of having a couple of kids) may have had an adaptive advantage. By engaging in "serial pair-bonding," they could vary the genetic make-up of their offspring. The timing of today's peaks in divorce rates may reflect the ingrained drive towards variation.
More recent research (Kulu, 2014) suggests that divorce rates rise after marriage and then peak at about five years. Rates of divorce then steadily decline as years together increase. This rising-falling pattern is reminiscent of the seven-year-itch argument but occurs slightly earlier (a five-year itch?) than the phrase suggests.
Time-based relationship vulnerability
It seems that a seven-year itch might be better named the four-year itch or the five-year itch, but even then, there's room for improvement. For instance, when do the seven (or four or five) years begin? Is it when a couple begins dating? Or is it when a couple gets married? The minimal research into this specific topic seems to assume a point of marriage; yet, couples often cohabitate prior to marriage, co-parent outside of wedlock, or never marry yet are fully committed to each other.
Even if relationship instability might crest at certain intervals, it's unlikely that time itself is the factor driving couple uncertainty, interest in other potential partners, or general distress. If external stresses tend to peak along a particular pattern (e.g., heightened financial or family stress), then those stresses (rather than time) would be worth our attention. Learning how to buffer couples from the adverse effects of external stress could help support their own smoother, more stable trajectory.
Facebook image: Marcos Mesa Sam Wordley/Shutterstock
References
Fisher, H. E. (1989). Evolution of human serial pairbonding. American Journal of Physical Anthropology, 78(3), 331-354.
Kulu, H. (2014). Marriage duration and divorce: The seven-year itch or a lifelong itch?. Demography, 51(3), 881-893.
Kurdek, L. A. (1998). The nature and predictors of the trajectory of change in marital quality over the first 4 years of marriage for first-married husbands and wives. Journal of Family Psychology, 494–510.
Lavner, J. A., & Bradbury, T. N. (2010). Patterns of change in marital satisfaction over the newlywed years. Journal of Marriage and Family, 72, 1171-1187.
