Alpha-fetoprotein (AFP) is a protein made by the yolk sac of a fetus. High levels in maternal blood can suggest potential genetic disorders such as spina bifida; low levels can indicate Down's syndrome.

A low sodium diet is a diet that includes no more than 1,500 to 2,400 mg of sodium per day.

Spermatogenesis is the process in which spermatozoa are produced from male primordial germ cells by way of mitosis and meiosis.