title: Family composition and menarcheal age: anti-inbreeding strategies.
abstract: Family composition (e.g., the absence of a father) is associated with pubertal timing in women, although the socioendocrinology of the human primate is poorly understood. To better understand social influences on sexual maturation, retrospective data were collected on menarcheal age and family composition from a sample of approximately 1,938 participants from a college population. Absence of a biological father, the presence of half- and step-brothers, and living in an urban environment were associated with earlier menarche. The presence of sisters in the household while growing up, especially older sisters, was associated with delayed menarche. Menarcheal age was not affected by number of brothers in the household, nor was there an effect of birth order. Body weight and race were also associated with menarche. The present findings advance the literature as they are suggestive of putative human pheromones that modulate sexual maturation to promote gene survival and prevent inbreeding, as occurs in rodents and nonhuman primates.
authors.affiliation: Department of Psychology, Altoona Campus, Pennsylvania State University, Altoona, Pennsylvania 16601, USA. rlm191@psu.edu
authors.forename: Robert L
authors.initials: RL
authors.lastname: Matchock
authors.forename: Elizabeth J
authors.initials: EJ
authors.lastname: Susman
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000704:Analysis of Variance; D001722:Birth Order; D001835:Body Weight / Q000502:physiology; D002648:Child; D003075:Coitus / Q000502:physiology; D003241:Consanguinity; D003710:Demography; D005191:Family Characteristics; D005219:Father-Child Relations; D005260:Female; D006801:Humans; D008572:Menarche / Q000502:physiology* / Q000523:psychology; D049049:Pheromones, Human; D012044:Regression Analysis; D012189:Retrospective Studies; D020954:Single-Parent Family; D012931:Social Environment; D012959:Socioeconomic Factors; D014505:Urban Population
chemical_list: D049049:Pheromones, Human