J Korean Med Sci.  2013 Jan;28(1):25-35. 10.3346/jkms.2013.28.1.25.

Social Inequality in Birth Outcomes in Korea, 1995-2008

• Park MJ
• Son M
• Kim YJ
• Paek D

• KMID: 2157997
• DOI: http://doi.org/10.3346/jkms.2013.28.1.25

Abstract

Social inequality in adverse birth outcomes has been demonstrated in several countries. The present study examined the separate and joint effects of parental education and work in order to investigate the causal pathways of social class effects on adverse birth outcomes in Korea. The occurrence of low birth weight, preterm births, and intrauterine growth retardation was examined among 7,766,065 births in Korea from 1995 to 2008. The effect of social inequality, as represented by parental education and work, was examined against adverse birth outcomes using multivariate logistic regression after controlling for other covariates. Parental education had the most significant and greatest effect on all three adverse outcomes, followed by parental work and employment, which had lesser effects. For adverse birth outcomes, the gap between educational levels increased steadily in Korea from 1995 to 2008. Throughout the analysis, the effect of maternal manual work on adverse birth outcomes was apparent in the study results. Given this evidence of social inequality in education and employment, social interventions should aim at more in-depth and distal determinants of health.

Keyword

Social Inequality; Parental Education; Parental Work; Parental Occupation; Birth Outcome Effect; Low Birth Weight; Preterm Birth; Intrauterine Growth Retardation

MeSH Terms

Adolescent
Adult
Educational Status
Employment
Female
Fetal Growth Retardation/*epidemiology
Humans
Infant, Low Birth Weight
Infant, Newborn
Logistic Models
Male
Middle Aged
Mothers
Odds Ratio
Parents
Premature Birth/*epidemiology
Republic of Korea/epidemiology
*Social Class
Time Factors
Young Adult

Figure

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  Fig. 1 Maternal age adjusted rates of low birth weight (LBW), preterm birth (PTB), preterm birth and low birth weight (PT_LBW), and intrauterine growth retardation (IUGR in Korea from 1995 to 2008. *Test for trend: P < 0.001 for LBW, PTB, PT-LBW, P = 0.051 for IUGR.

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  Fig. 2 Adjusted odds ratios of low birth weight (LBW), preterm birth (PTB), preterm birth and low birth weight (PT_LBW), and intrauterine growth retardation (IUGR), adjusting for infant sex, maternal age, parental age, multiple births, parity, death of previous children, and year of birth in Korea from 1995 to 2008.

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