Thymo-Pause or immunological climacteric refers to the period of time during which the thymus gland undergoes a drastic decline
During this period the immunological memory cells can no longer counteract the effects of the reduction in thymic hormones which occur during the third and fourth decades of life, and an increasing sensitivity to infections and neoplasia (malignancies) takes place. Wechsler et al. (1978) believes that the level of function of the immunological defense system determines the age which human beings are capable of attaining.