Effect of Season of Birth and Some Related Variables on Birth-Weight in Children Who Admitted to Health Care of West Ahvaz

Birth-weight is affected by many factors. Some studies have shown that season of birth may be affected on birth-weight. However، there is less information about this effete mechanisms underlying. This study was carried out to define the relationship among birth weight and season of birth and some related factors. This analytical cross-sectional study was held on 808 children under one year old who were attended to health centers of west of Ahvaz in 2008. Samples were randomly selected in two stages. Data were gathered through questionnaire and were analyzed by the means of statistical SPSS software version 17، Chi-Square and Pearson correlation tests، ANOVA، and linear regression. P value less than 0. 05 was considered statistically significant. Mean birth-weight was 3273. 5±525. 4، 3251. 6±421. 3، 3280. 5±547. 6 and 3192. 9 ±518. 4 gram in spring، summer، autumn and winter respectively. Although there was no significant correlation between these variables، a seasonal rhythm in mean birth-weight was observed. The rates of low birth weight were 4. 9% with highest rate (6. 5%) in winter. The relationship between birth-weight and other variables such as sex، birth rank، maternal age، and weight gain in pregnancy were significantly positive (p<0. 05). In regards to the findings، improvement of proper and efficient prenatal care، educational and interventional programs focusing on gestational weight-gain and special care of nuliparous women can play an important role in increasing birth weight.