A large international study suggests that changing hormonal contraceptive use during a relationship is not associated with meaningful reductions in women’s love for their partners or overall relationship satisfaction. The findings challenge a debated hypothesis proposing that changes in contraceptive status could alter romantic preferences and relationship quality.
The study, titled Hormonal contraceptive use is associated with love intensity across 51 countries, was conducted by Marta Kowal, Piotr Sorokowski, Michał Misiak, W. P. Malecki, Agnieszka Sorokowska and S. Craig Roberts, with support from the IDN Being Human Lab at the University of Wrocław. Published in Scientific Reports, the research analyzed 2,224 women in ongoing relationships from a broader international sample of 10,482 participants across 51 countries.
Women provided information about their current and previous hormonal contraceptive use, including whether they were using hormonal contraception when they first met their partner, alongside measures of their feelings about their relationships.
Why hormones and love were linked
Hormonal contraceptives alter reproductive hormonal patterns through mechanisms that vary by method. Because sex hormones can influence processes related to mood and sexual functioning, researchers have investigated whether hormonal contraception might also be associated with romantic attraction and relationship experiences.
Earlier studies raised the possibility that women’s contraceptive status when they met a partner could be related to subsequent relationship satisfaction. One influential proposal became known as the Congruency Hypothesis.
According to this hypothesis, consistency in hormonal contraceptive status might matter. Women who met a partner while using hormonal contraception and subsequently stopped, or who began using it after meeting their partner, could theoretically experience changes in preferences that influence how they perceive that partner.
Evidence supporting this idea, however, has been mixed, and the new study tested whether the proposed pattern could be detected across a much larger and more internationally diverse sample.
A global test of the congruency hypothesis
Researchers used semi-representative samples from 51 countries, substantially expanding beyond the predominantly Western populations examined in much previous research.
They focused on women aged 45 or younger who were currently in relationships and could report their hormonal contraceptive status both when they met their partner and at the time of the survey. Participants were approximately 32 years old on average, and their relationships had lasted around eight years.
Women completed measures of intimacy, passion and commitment based on the Triangular Theory of Love framework. They also rated their overall relationship satisfaction and provided information about factors including relationship duration and socioeconomic status.
Little evidence that contraceptive changes erode love
Among the participants, 1,611 women had maintained the same hormonal contraceptive status since meeting their partner, while 613 had changed status by either starting or stopping hormonal contraception during the relationship.
The researchers found no robust differences between these groups in relationship satisfaction, intimacy or commitment. Women whose contraceptive status had changed generally reported comparable levels of closeness, commitment and relationship satisfaction to women whose status remained consistent.
The analyses also provided little evidence that current hormonal contraceptive use was associated with poorer overall relationship quality. Current users generally reported similar relationship outcomes to non-users.
These findings provide little support for the central prediction of the Congruency Hypothesis, at least for relationship outcomes and effect sizes detectable in this sample.
A small passion signal, with caveats
One analysis identified a very small difference in passion among women whose contraceptive status had changed, corresponding to approximately 1.6% lower passion on average.
However, this association was not consistent across analyses and was described as borderline and fragile. It therefore provides weak evidence for a meaningful relationship between contraceptive change and passion.
Relationship duration represents one possible explanation for the pattern. Passion can change over the course of long-term relationships, while women in longer relationships also have more time in which to start or stop hormonal contraception.
Because the research was cross-sectional and relied partly on retrospective reports, it cannot determine whether contraceptive changes caused any differences in passion. Longitudinal research following the same women before and after contraceptive changes would provide stronger evidence.
Cross-country differences and limitations
Hormonal contraceptive use varied substantially across the 51 countries. Current use ranged from approximately 71% in Honduras to 3% in India.
Such differences can reflect numerous factors, including contraceptive availability, healthcare systems, personal preferences and cultural circumstances. The study was not designed to determine why prevalence differed between individual countries.
The largely null results also do not establish that hormonal contraception can never influence an individual woman’s mood, sexuality or relationship experiences. Rather, the study found little evidence for the specific prediction that changing contraceptive status systematically reduces love or relationship satisfaction across women.
Selection effects remain possible because women who start, stop or continue hormonal contraception may differ in other characteristics related to their relationships. Participants also had to remember whether they were using hormonal contraception when they first met their partners, creating potential for recall error.
What this means for women’s choices
At the population level, the findings offer little support for the idea that changing hormonal contraceptive status during a relationship meaningfully weakens love or relationship satisfaction.
However, population averages cannot predict how an individual woman will respond to a particular contraceptive method. Experiences involving mood, sexual desire or other effects can vary, and contraceptive decisions involve considerations beyond relationship satisfaction.
The researchers call for longitudinal studies that follow women through contraceptive changes over time. Such research could better distinguish possible hormonal effects from relationship duration, individual differences and other life circumstances.
For now, the findings challenge the suggestion that women should expect their feelings toward an established partner to deteriorate simply because they start or stop hormonal contraception. Across this large international sample, changing contraceptive status was not robustly associated with lower intimacy, commitment or overall relationship satisfaction.
