The interaction between emotional stress and infertility has been investigated for many years. Many infertile couples show marked stress during infertility evaluation and treatment. Most of the investigations that were performed during the last two decades show that in the majority of cases stress is the result and not the cause of infertility. The biological interaction between stress and infertility is the result of the action of stress hormones at the brain level, especially on the hypothalamus-pituitary and on the female reproductive organs. Stress hormones such as catecholamines (adrenalin, nonadrenaline and dopamine) and the hypothalamic-pituitary-adrenal axis interact with hormones which are responsible for normal ovulatory cycles: i.e., gonadotropin releasing hormone (GnRH), prolactin, LH and FSH. Endogenous opiates and melatonin secretion are altered by stress and interfere with ovulation. Sympathetic innervation of the female reproductive system provides routes by which stress can influence fertility at the of the sex organs level. Infertility causes stress which is aggravated as time passes and the couple remains infertile. Among the causes of stress are the couple's isolation, life with unrealized potential and unborn child, disruption of day-to-day life during infertility evaluation and treatment, and the couple's feeling that they do not have control of their own lives. The IVF program is considered by many as the final step for the evaluation of the couples fertility potential, hence, couples participating in an IVF program are highly stressed, especially after a failed IVF cycle.