The syndromes of isolated gonadotropin deficiency

Six theoretically possible syndromes of IGD are shown in Table 1. 1) IBGD is well-substantiated both in males and in females, and appears to be either of pituitary or more frequently of nonpituitary origin. 2) An example of isolated FSH deficiency has been described. The defect appears to reside at the pituitary level and may be localized to the FSH beta subunit. Recently a male patient has been studied with isolated FSH deficiency and a concordant testicular picture viz germinal cell aplasia. However, the syndrome is complicated by an associated chromosomal abnormality (XO/XXY/XY) whose significance is unclear. 3) Several examples of isolated hLH deficiency have been described. Several questions remain about the exact nature of the defect in some of the published reports of this syndrome.