Maya symbols associate cultural interpretations of biological reproduction with gender roles within a cosmological model of the natural world. These traditional symbols were used in a ceremony performed to cure the pubescent daughter of a modernizing family. She was suffering “ataques de nervios” (nervous attacks, including muscle spasms and loss of consciousness) believed to be caused by a delay in the onset of menarche. Analysis of the symbols relied on multiple approaches that allowed decoding of ceremonial symbols as references to (1) the gendered pairing of marriage, (2) the social reproduction of gender through the generations, (3) the reproductive aspects of human bodies as symbols of interdependency, and (4) maleness and femaleness as primary forces of the Maya cosmos. The traditional symbols, combined with the teachings of the healer, provided an interpretation of the biological differences between male and female bodies within an overarching cosmological system. The primary symbols referred explicitly to male and female genitalia and menstrual blood as symbols for the reproduction of gender through generations of mothers and daughters, fathers and sons. The ceremony was apparently effective-despite a context of rapid modernization in which family planning, formal education, and new economic opportunities increasingly result in employment of women outside the home.