Explaining Educational Inequalities in Preterm Birth. The Generation R Study

Pauline Jansen ^1*, Henning Tiemeier ², Vincent Jaddoe ², Albert Hofman ², Eric Steegers ², Frank Verhulst ², Johan Mackenbach ² and Hein Raat ²

¹ Erasmus MC-University Medical Center Rotterdam, Netherlands
² Erasmus MC-University Medical Centre Rotterdam, Netherlands

^* To whom correspondence should be addressed. E-mail: p.w.jansen{at}erasmusmc.nl.

Accepted 26 May 2008

Abstract

Background: Although a low socioeconomic status has consistently been associated with an increased risk of preterm birth, little is known about the pathways through which socioeconomic disadvantage influences preterm birth.

Aim: To examine mechanisms that might underlie the association between the educational level of pregnant women as an indicator of socio-economic status, and preterm birth.

Methods: The study was nested in a population-based cohort study in the Netherlands. Information was available for 3830 pregnant women of Dutch origin.

Findings: The lowest educated pregnant women had a statistically significant higher risk of preterm birth (OR=1.89 [95% CI: 1.28, 2.80]) than the highest educated women. This increased OR was reduced by up to 22% after separate adjustment for age, height, pre-eclampsia, intrauterine growth restriction, financial concerns, long lasting difficulties, psychopathology, smoking habits, alcohol consumption, and BMI of the pregnant women. Joint adjustment for these variables resulted in a reduction of 89% of the increased risk of preterm birth among low educated pregnant women (fully adjusted OR=1.10 [95% CI: 0.66, 1.84]).

Conclusions: Pregnant women with a low educational level have a nearly two-fold higher risk of preterm birth than women with a high educational level. This elevated risk could largely be explained by pregnancy characteristics, indicators of psychosocial well-being, and lifestyle habits. Apparently, educational inequalities in preterm birth go together with an accumulation of multiple adverse circumstances among women with a low education. A number of explanatory mechanisms unravelled in the present study seem to be modifiable by intervention programs.