Objective: To examine whether gender-specific physiologic differences are present at birth and can be a basis for gender-specific vulnerability to developmental disorders in males. We report on three studies of male-female physiologic and structural differences in neonates and their relevance to observed differences in the incidence of developmental disorders in males. Methods: Study I: 56 neonates were examined for cardiac reactivity to the Moro reflex. Study II: 863 neonates' basic anthropometric data were examined to demonstrate gender-specific differences in body proportions as a possible basis for psychophysiologic differences. Study III: Developmental data on 1000 one-to 26-week-old infants were analyzed for gender-specific developmental differences in rhythmic patterns of sleeping and eating. Results: Study I: There were gender-related differences in heart rate reactivity (male > female). Study II: Male newborns had significantly larger head/chest proportions, suggesting that they may have a greater metabolic demand, related to brain size. Study III: Mothers reported that infant males' sleeping rhythm developed significantly later than females', and that they slept for shorter periods at night. Conclusions: Gender-related vulnerability in brain development is proposed, based on physiologic differences during a specific early sensitive period in development. This hypothesis may help to explain the overrepresentation of males reported for most developmental disorders.
|Number of pages||9|
|Journal||Journal of Gender-Specific Medicine|
|Publication status||Published - May 26 2001|
ASJC Scopus subject areas
- Pathology and Forensic Medicine