|This case-control study was aimed to identify a relationship between maternal factors and low birth weight of the newborns. The data were collected by an oral interview together with data collection form. Subjects were mothers who delivered newborn babies with normal weight ( 2500 grams) and low birth weight (< 2500 grams) at Roi-Et Hospital during March – July 2005. The study was conducted using case-control with a proportion of 1: 4. Thus, there were 200 and 800 subjects who delivered newborns with normal birth weight and low birth weight, respectively. Logistic regression analysis and chi-square (2) test were used to analyze the data. The results revealed that the following maternal factors; age, occupation, height, weight gain during pregnancy, pre-eclampsia (high blood pressure), premature rupture of membranes (rupture of amniotic sac before a baby is due date), bleeding during pregnancy, gravida (single or twin pregnancy) and standard antenatal care of at least four visits were significantly related to low birth weight of the newborns (p-value <0.05 and <0.01). In addition, several factors were capable to explain the changes of weight of newborns as follows: 1) weight gain during pregnancy 2) rank of pregnancy 3) premature rupture of membranes 4) frequency of miscarriage 5) hemoglobin level 6) gravida 7) bleeding 8) pre-eclampsia and 9) standard visits of antenatal care. This was summarized in the following equation:
ŵ = 92.305 – (1.502* standard visits of antenatal care) + (0.214* weight gain during pregnancy) + (0.494* rank of pregnancy) - (0.789* miscarriage) + (0.306 * hemoglobin level) + (1.698* pre-eclampsia) + (3.453* premature rupture of amniotic sac) + (2.858 * bleeding during pregnancy) – (2.551* gravida)
Additionally, the result showed that factors affected the odd ratio of having newborn with low birth weight were standard antenatal care, frequency of miscarriage and gravida.