Genetic causes and workup of male and female infertility. 2. Abnormalities presenting between birth and adult life.

At birth some 6/1,000 persons have chromosome abnormalities; in about 60% of cases these abnormalities cause death or infertility, and in one third fertility is reduced. Some 1.7% of persons (3.4% of couples) with recurrent spontaneous abortion, infertility, or both have a chromosome abnormality. Chromosome abnormalities are far more common in men than in women with infertility; 15% to 20% of men with azoospermia have the Klinefelter syndrome. Meiotic defects explain 20% of male infertility in patients with apparently normal somatic chromosomes. Congenital malformations of the genitalia are more common in males than in females; about 0.82% of liveborn males have hypospadias. Almost one sixth of women with primary amenorrhea have some form of müllerian atresia, usually with associated renal anomalies.