[The influence of social and health factors including pregnancy weight gain rate and pre-pregnancy body mass on low birth weight of the infant].

OBJECTIVES

to investigate the influence of social and health factors on low birth weight (LBW) among Polish women. LBW is defined as birth weight less than 2500 g.

MATERIALS

27,015 perinatal data gathered from 40 Polish hospitals taking part in the OBSQID international project.

METHODS

Descriptive statistics and multifactorial logistic regression. Dependent variable: LBW.

INDEPENDENT VARIABLES

maternal age, place of residence, marital status, education, parity, smoking, diseases before and during pregnancy, obstetrical history, pregnancy weight gain rate, prepregnancy BMI.

RESULTS

6.4% LBW in all neonates, 2.0% LBW in full term neonates were ascertained. Among vaginal deliveries, increased risk of LBW have: underweight (OR=2.2); small pregnancy weight gain rate (OR=2.2); unmarried (OR=1.9); multiparous (OR=1.5); elementary education (OR=2.7); professional education (OR=2.3), mother age less than 20 years (OR=1.5); smoking before pregnancy (OR=1.7). Among cesarean section deliveries increased odds have: small pregnancy weight gain rate (OR=2.9), residence in town (OR=2.0), elementary education (OR=4.4); professional education (OR=2.8). LBW odds ratio for small pregnancy weight gain rate jointly with prepregnancy low BMI due to other factors was considerably high (OR=7.1 for vaginal delivery, OR=2.6 for cesarean section).

CONCLUSIONS

prepregnancy low BMI together with small pregnancy weight gain rate is an important risk factor for LBW. Mother age (under 20 years of age) decreases the risk of LBW.