Previous research on contemporary childbearing has identified a strong relationship between environmental conditions, such as economic deprivation, and early fertility. Less is known, however, about the social-psychological mechanisms that mediate these environmental predictors of early fertility at the individual level and the extent to which they are consistent with life history theory. The aim of this research was to determine how kin networks, mating and reproductive risk taking, discount preference, and perceptions of environmental risk predict individual differences in fertility preferences in a socioeconomically diverse sample of adolescents. Questionnaires were administered to 333 adolescents (245 female) between the ages of 13 and 19 years, attending schools in urban neighborhoods in Hampshire, United Kingdom. Individuals’ subjective life expectancy and perception of their environment better predicted fertility intentions than did structural measures of environmental quality. This suggests that by the time individuals reach adolescence they are monitoring the morbidity and mortality risk of their environment and are adjusting their reproductive ideals accordingly. Levels of grandparental investment also predicted parenting preferences, suggesting cooperative breeding may play a role in reproductive decision making. There was also evidence that patterns of risk taking behaviors could be adaptive to environmental conditions and some evidence that pro-natal attitudes, as opposed to knowledge of safe sexual practice, predict adolescents’ reproductive strategies. These findings suggest that studying individuals’ psychology from a life history perspective adds to my understanding of the persistently high rates of early reproduction within developed countries, such as the United Kingdom.