Social differences in reproductive health. A study on birth weight, stillbirths and congenital malformations in Denmark

Abstract

Aim: To describe differences in life style variables according to socioeconomic groupings and to analyse the association between birth weight, stillbirth and congenital malformation according to the socioeconomic grouping for the father as well as the mother.

Method: Follow-up of 11,888 pregnant women in Odense and Aalborg, Denmark who were consecutively enrolled in the study from April 1984 to April 1987 as part of a community trial.

Data: Information on socioeconomic group and life-style factors were collected by means of self-administered questionnaires in the 36th week of gestation. Data on pregnancy outcomes were collected from birth certificates and medical records according to standardized search routines.

Results: Women in the lower socioeconomic groups were younger, smaller, had a higher prepregnancy weight, smoked more and had a higher intake of coffee during pregnancy than women in higher socioeconomic groups. Better off women, on the other hand, had a higher consumption of alcohol, fish, and vegetables. Low birth weight was found to be negatively correlated with socioeconomic grouping. The lowest birth weights were found among babies born to unskilled and unemployed women even after adjustment for smoking habits, prepregnancy height and weight and a number of other potential confounders. Stillbirth and the prevalence of congenital malformations was not associated with socioeconomic grouping, but the amount of information was very limited regarding these outcomes.