Genetic risk assessment should be based
on family history, paternal age, and ethnicity.
A 3-generation family history of
genetic disorders should be obtained, as
certain disorders (sex-linked or autosomal
recessive) may skip generations. A
number of genetic disorders, such as cystic
fibrosis, Klinefelter syndrome, Kartagener
syndrome, and polycystic kidney
disease, may impair fertility and sperm
quality. In a review article on Klinefelter
syndrome, the study authors collected
data consistent with symptomatic
azoospermia, and only 8.4% of their
adult patients had spermatozoa in their
ejaculate, out of the 69.3% of their population
that were willing and able to provide
an ejaculate sample.9 A small study
of pre- and peripubertal boys with
Klinefelter syndrome found that half (7)
of the subjects had no spermatogonia;
this study also found an association between
the beginning of puberty and loss
of spermatogonia