Pregnant women are more susceptible to vaginal yeast infections, most likely due to changes in hormones during pregnancy. Cushing disease and diabetes mellitus impair immunological function, putting patients with these conditions at higher risk for opportunistic infections. Systemic antibiotics alter the normal regulatory balance of microorganisms, enabling normally found organisms to become pathogens. Children over the age of one are not particularly susceptible to yeast infections, as they have established immune reactivity. Alternatively, infants under six months of age are more susceptible due to decreased immune reactivity.