TNF and infection: In fact, there is a ‘hierarchy of sensitivity,’ with TNF-α being the most sensitive to such inhibition at the physiologic level, IL-1β being second and IL-6 being the most resistant.20 Thus, mothers undergoing stressful conditions (for example, obstetric complications, trauma, chronic social stress and certain infections) would be expected to produce excess maternal glucocorticoids that would inhibit TNF-α responses (that is, the most physiologically sensitive cytokine to HPA axis activation20).