Each month, millions of women experience an ovulatory cycle that regulates fertility. Previous consumer research has found that this cycle influences women's clothing and food preferences. The authors propose that the ovulatory cycle actually has a much broader effect on women's economic behavior. Drawing on theory in evolutionary psychology, the authors hypothesize that the week-long period near ovulation should boost women's desire for relative status, which should alter their economic decisions. Findings from three studies show that women near ovulation seek positional goods to improve their social standing. Additional findings reveal that ovulation leads women to pursue positional goods when doing so improves relative standing compared with other women but not compared with men. When playing the dictator game, for example, ovulating women gave smaller offers to a female partner but not to a male partner. Overall, women's monthly hormonal fluctuations seem to have a substantial effect on consumer behavior by systematically altering their positional concerns, a finding that has important implications for marketers, consumers, and researchers.