PLOD1 and Hypergonadotropic hypogonadism: Based on both LH and total T serum levels the prevalence of biochemical hypogonadism, defined as serum T<300 ng/dL or an inappropriately high serum LH value with normal serum T, (comprising patients with compensated, secondary and primary hypogonadism) increased from 16% to 30% (Figure 2, Table 4).