Abstract

Recently, a multitude of psychology studies have discovered menstrual cycle changes in a variety of preferences and behaviors in women. However, no study to date has investigated whether or not the menstrual cycle influences consumer behavior. Based on evolutionary theory and behavioral physiology findings, it was hypothesized that women would (1) engage in more consumption associated with food, cleaning, home, health, and gift-giving during the luteal phase when progesterone and immunosuppression levels are elevated, and (2) engage in more appearance-related consumption during the follicular phase when estrogen and fertility levels are highest. Thirty-five normally cycling women were asked to track their purchases and complete online surveys every evening for 35 days. Analyses revealed significant differences between consumption levels reported on luteal days and on fertile days. On luteal days, women exhibited increases in various food consumption measures and amount of money spent on food. Results also show that women spend more money on health-related products, and have a greater desire to spend money on home-related products and on gift-giving during the luteal phase. Regarding appearance-related consumption, results suggest a stronger desire to spend money on clothes, shoes and/or accessories on fertile days in partnered women. This paper contributes to the marketing literature in four key ways. First, managerial implications are discussed, including potential product placement and data mining strategies. Second, the results constitute the first evidence of a hormonal driver of shopping behavior. Third, the findings contribute to the growing research stream focused on consumer welfare. Finally, this thesis promotes a novel research stream that unites the fields of biology and consumer behavior.