Preconception selection of sex in man.

The determination of sex is influenced by ionic factors. In man, ionic imbalance is responsible for the sex ratio in at least 80% of cases, the possible mechanism being one of selective fertilization. These facts constitute the scientific basis for the medicodietary method of selecting sex.

[Ovarian calcium and fertilization in female rats receiving a subchronic overdose of vitamin D3].

Calcium is increasing in ovaries of adult female rats when D3 vitamin is given by stomach intubation for 7 and 15 days. Histochemical studies show the presence of spherular chalky deposits specially in granulosa of some follicles. In the same times atresia becomes evident and fecondation is reduced.

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.

[Magnesium in animal and human reproduction].

The literature concerned with the amount of magnesium in genital organs and products of sexual activity is analysed in the first chapter; these data are compared with those concerning other organs and replaced in a comprehensive view of the body, related or not with the medium. It is likely that magnesium plays a role in ovule maturation, sperm viability and fecundation in Invertebrates and Fishes. In Birds and Mammals, it appears to be necessary for fecundation.