Preconceptional selection of fetal sex.

Background information is given on postconceptional and preconceptional methods of selecting fetal sex. Among the preconceptional methods presented are treatment of the sperm to isolate either the X or the Y chromosome, timing of insemination and the effect of ionic concentrations in the woman's body as controlled by the dietary intake of minerals. The authors studied 281 couples, 21 of whom were later excluded, who adhered to a diet specific in its amounts of calcium, magnesium, sodium and potassium. This dietary method of preconceptional selection of fetal sex resulted in the anticipated outcome in about 80% of the cases.