Οι εποχικές κυμάνσεις στο βάρος και το φύλο του παιδιού κατά την γέννηση
Παρασχόπουλος, Παναγιώτης Α.
Studies have shown that the child’s sex at birth and the child’s weight at birth affected by seasonal variation in conception. The purpose of this paper is to investigate if the seasonality of conception affects the sex of the child at birth and the weight of the child at birth. The theoretical analysis based on Greek and international literature. The theoretical analysis showed that seasonal variation differs from the latitude and mainly by two factors associated with it, the ambient temperature and sunlight. Especially for the birth weight, analysis must differentiated by whether it is for developing or developed countries, where at first dominated by the effects of living standards that go beyond any effects of seasonality. Our data derived from birth registration in Greece in 2006. We applied logistic regression model for the effect of seasonality at conception to the child's sex at birth and one way analysis of variance models for the effect of seasonality in conception to the child's weight at birth. The application of the Logistic Regression model showed that month of conception October increase the odds having a girl and show no effect at the child's sex from the season of conception. The application of one way analysis of variance models have showed that autumn months of conception give lower mean weight at birth. Perhaps the effect of low winter temperatures during the second trimester of pregnancy, when conception takes place in October, to operate biased in favor of female embryos. Similarly the effect of low temperatures of winter, when conception takes place in autumn months, seems to cause lower mean birth weight. Similar effects have been demonstrated also from studies in countries with similar latitude with Greece.