In 2001, researchers Leonie Welberg and Jonathan Seckl published the literature review “Prenatal Stress, Glucocorticoids, and the Programming of the Brain,” in which they report on the effects of prenatal stress on the development of the fetal brain. The fetus experiences prenatal stress while in the womb, or in utero. In discussing the effects of prenatal stress, the authors describe prenatal programming, which is when early environmental experiences permanently alter biological structure and function throughout life. Throughout “Prenatal Stress, Glucocorticoids and the Programming of the Brain,” Welberg and Seckl provide a number of potential biological explanations, derived from both animal and human studies, to explain the underlying mechanisms involved in programming, which helped establish how in utero stress can affect fetal brain development.