Abstract:
Background: The epidemiological evidence linking socioeconomic deprivation with adverse pregnancy outcomes has been
conflicting mainly due to poor measurement of socioeconomic status (SES). Studies have also failed to evaluate the
plausible pathways through which socioeconomic disadvantage impacts on pregnancy outcomes. We investigated the
importance of maternal SES as determinant of birth weight and gestational duration in an urban area and evaluated main
causal pathways for the influence of SES.
Methods: A population-based cross-sectional study was conducted among 559 mothers accessing postnatal services at the
four main health facilities in Cape Coast, Ghana in 2011. Information on socioeconomic characteristics of the mothers was
collected in a structured questionnaire.
Results: In multivariate linear regression adjusting for maternal age, parity and gender of newborn, low SES resulted in
292 g (95% CI: 440–145) reduction in birth weight. Important SES-related determinants were neighborhood poverty (221 g;
95% CI: 355–87), low education (187 g; 95% CI: 355–20), studentship during pregnancy (291 g; 95% CI: 506–76) and low
income (147 g; 95% CI: 277–17). In causal pathway analysis, malaria infection (6–20%), poor nutrition (2–51%) and indoor air
pollution (10–62%) mediated substantial proportions of the observed effects of socioeconomic deprivation on birth weight.
Generalized linear models adjusting for confounders indicated a 218% (RR: 3.18; 95% CI: 1.41–7.21) risk increase of LBW and
83% (RR: 1.83; 95% CI: 1.31–2.56) of PTB among low income mothers. Low and middle SES was associated with 357% (RR:
4.57; 95% CI: 1.67–12.49) and 278% (RR: 3.78; 95% CI: 1.39–10.27) increased risk of LBW respectively. Malaria infection, poor
nutrition and indoor air pollution respectively mediated 10–21%, 16–44% and 31–52% of the observed effects of
socioeconomic disadvantage on LBW risk.
Conclusion: We provide evidence of the effects of socioeconomic deprivation, substantially mediated by malaria infection,
poor nutrition and indoor air pollution, on pregnancy outcomes in a developing country setting.
