Influence of environmental temperatures during gestation and at birth on eating characteristics in adolescence: a replication and extension study.

Past research has shown a season of birth effect in clinical subjects with eating disorders. Studies also indicate a similar effect of environmental temperatures in non-clinical subjects, as well as effects of environmental temperatures during the three trimesters of gestation. These two studies aimed to replicate and extend those findings. The participants were adolescents (ages 15-19 years) who attended public schools in a mid-Atlantic US city. They completed the relevant scales of the Eating Disorder Inventory (N=578) and the Three Factor Eating Questionnaire (N=191). Correlational analyses were employed to study the relationship of environmental temperatures during pregnancy (the three trimesters of intrauterine development and at birth) with eating characteristics. The results of the previous studies were broadly replicated in Study 1, but Study 2 revealed a difference in the pattern of associations according to the measure used. This contrast indicates that the way in which one conceptualizes eating pathology is of critical importance in understanding the long-term impact upon eating patterns of environmental temperature during the intrauterine period. Possible theoretical bases for these findings are discussed.