Early Stage Romantic Love is Associated with Reduced Daily Cortisol Production

Early-stage romantic love constitutes a unique phase associated with distinct brain activations and neuro-hormonal processes that function to consolidate the affiliative bond. Little research addressed functioning of the hypothalamic-pituitaryadrenal (HPA) axis during this phase or tested the relationship between cortisol and interactive behavior in new lovers. The current study examined daily cortisol production in 113 healthy young adults, including 79 new lovers who began a romantic relationship within the past 3 months and 34 demographically-matched singles. Saliva samples were collected three times per day on two consecutive days: at awakening, 30 minutes post-awakening, and at bedtime. Couples were videotaped during naturalistic interactions and self-reported on their relationship quality. Basal cortisol, total daily cortisol (AUCg), and cortisol awakening response (CAR) were assessed. New lovers exhibited lower daily cortisol production and blunted CAR, suggesting that the initiation of a romantic bond attenuates the stress response. Observed social reciprocity and goal-directed partnership and reported commitment to the relationship were associated with lower daily cortisol. Findings are consistent with research on the effects of intimate partner relationships on the stress response and support our bio behavioral synchrony model by demonstrating links between neuroendocrine processes and reciprocal social behavior during periods of bond formation in humans.