For many parents-to-be, pregnancy is an exciting and joyful time. However, it can also be a stressful time, whether stress is a preexisting issue that precedes pregnancy or comes from uncertainty and anxiety surrounding childbirth and child-rearing. Past research showed that prenatal stress and anxiety, particularly that of expectant mothers, can have adverse effects on infant temperament. Stressors during pregnancy are not only mothers’ (or parents’) psychological issues but also external factors such as teratogens (e.g., cigarettes, alcohol, drugs) that create a toxic prenatal environment for a developing fetus, which in turn creates long-lasting consequences for the offspring.