Certain steroids can react with proteins to form stable, covalent addition products. 16α‐hydroxyestrone and the glucocorticoids, for example, contain ketol moieties which permit them to react non‐enzymatically with proteins by forming Schiffbase rearrangement products with lysine residues. The oral contraceptive agent, 17α‐ethinylestradiol, can add to proteins after being enzymatically activated by microsomal oxidation. Elevated plasma levels of these steroids result in an increased amount of protein modification in vivo. Recent investigations have linked the occurrence of steroid‐modified proteins with pathological (...) sequelae associated with high steroid levels. (shrink)

This paper defends the hypothesis of a potential causal link between increased usage of hormonal contraceptives (HCs) and significant rises in instances of Autism Spectrum Disorders (ASDs) worldwide. It develops a background theory that supports this hypothesis through analysis of: observed correlations between increased usage of HCs and increased instances of ASDs; consistent evidence from independent studies linking “birth spacing” intervals and ASD-risk; evidence from studies on the effects of HCs on folate and B12 absorption; and hypotheses concerning disruptions to (...) mechanisms of delivery of folate and B12 during periods of in utero brain development. The proposed theory is then defended through discussion of how it may explain numerous puzzling correlations with increased instances of ASDs documented in certain demographics. (shrink)