A Case-control Study On Influencing Factors Of Low Birth Weight In Rural Areas

Objective: To investigate incidence of low birth weight (LBW) in rural areas of Yunnan province, to explore correlation factors of LBW, and to provide scientific basis for developing appropriate intervention strategies and measures for LBW.Methods: In this study, LBW monitoring was carried out in Xiangyun County, Yunnan province. Between 1st Jan, 2007 and 31st Dec, 2007, there were totally 2734 women with newborn enrolled in our study site. Among them there were 170 cases of LBW. In analytical study, 1:2 matched case-control study was conducted. 170 cases of LBW were set as case group, and 340 strictly matched cases of normal delivery parturients were selected as control group. The paired conditions were maternal age, parity, family economic status, and inhabited area. Database was founded and processed by using SPSS software packages. Conditional logistic regression model was used to explore correlates of LBW.Results: The incidence of low birth weight is 7.97% in poor rural areas of Xiangyun County. In single factor analysis, nationality of mother and father, type of the family, mother's height, pre-pregnancy weight of mother, LBW history of family, chronic diseases history before pregnancy, abortion history, preterm delivery history, stillbirth history, times of prenatal examination, delivery site, gender of baby, gestational weeks, food consumption amount during pregnancy, serious pregnancy reaction, and body weight gain during pregnancy, were significantly associated with LBW. In multiple factors analysis, backward stepwise regression was used to fit the main effects of equation. The results shows that maternal height, body weight gain over 6.9Kg during pregnancy, prenatal examination over 5 times during pregnancy, and longer pregnancy duration were protective factors of LBW, while serious pregnancy reaction, chronic diseases history before and during pregnancy, give delivery at township hospital, and preterm delivery were risk factors of LBW. Main effects equation was built up as:lnOR=1.309X₁₅+1.208X₁₆+0.922X₂₂+0.673X₁₈+0.554X₁₄-0.066X₇-0.180X₁₇-0.358X₁₉-2.048X₂₀Conclusion: The incidence of LBW in rural areas of Xiangyun County is higher than that of national and provincial average level. In this region, main influencing factors of LBW are maternal health status, maternal health care, and maternal nutritional status before and during pregnancy. This reminds us that, publicizing eugenic, health care and nutritional knowledge during pregnancy, enhancing health care awareness of residents in poor rural areas, changing single dietary pattern of pregnant mothers, and increasing pre-pregnancy and prenatal medical check and screening, would surely relieve LBW burden in the area.