[Social class and birth weight]. / Sosial klasse og fødselsvekt.

The aim of this study was to investigate whether the birthweight of Scandinavian children varies according to the social class of their parents, especially the mother. Data were taken from the Scandinavian part of an international multicentre study of fetal growth and perinatal outcome. The occupations of the pregnant woman, her spouse and her parents were registered according to the Nordic classification of occupations. This classification has been criticised for being too detailed to be suitable in epidemiological studies, and the data were recorded into the British system of five classes. The birthweight of female newborns in social class V was 301 g lower than in the other social classes (p < 0.05). A corresponding difference was not shown among male newborns. Newborns of women that had migrated downwards in the socioeconomic system, were 117 g lower than if the migration was upwards (p < 0.05). This difference among female newborns was 164 g (p < 0.05). This study demonstrated that there are differences in birthweight according to social class. This may partly be due to genetic factors and a higher prevalence of smoking and high body mass index, i.e. a less favourable lifestyle in the lower social classes.

Occurrence of injuries in a defined population.

A 1-year study of all registered accidents was carried out. All patients treated for an injury at the Trondheim University Hospital, Norway, were recorded. This is the only institution in the region treating injuries. Hence, this is a total injury registration in a defined population. The incidence rate was 114 injuries per 1000 inhabitants. Home accidents were the most common type. Accidents occurring at institutions, in traffic areas and at home caused the longest hospitalization. Most of the injuries were minor; 0.4 per cent of the accidents were fatal. Traffic accidents and home accidents were responsible for the highest percentage of fatal accidents. The demand for preventive measures and reduction of accidents has been based on mortality rates in comparable studies. The mortality rate is well reported for most of the civilized world but this does not tell us anything about the morbidity rate due to accidents. By reducing the accidents needing the longest hospitalization, the economic consequences for the national health system would also be decreased.

Randomised controlled trial of ultrasonographic screening in pregnancy.

510 of 1009 pregnant women in the Trondheim area (Norway) were randomly selected for ultrasound examination at the 19th and 32nd weeks of pregnancy in addition to routine antenatal care. Among the screened women, twins were diagnosed earlier and there were slightly fewer post-term inductions (2.8% versus 4.0%) and fewer low-weight births (2.2% versus 3.6% less than 2500 g), but none of these differences was statistically significant. There were no differences in the condition of the newborn. Small-for-gestational-age births were more often diagnosed antenatally in the screened group and the mothers received more active treatment. During pregnancy, screened women were admitted to hospital more often than unscreened women (15.5% versus 9.2%). The study revealed no adverse short-term biological effects from ultrasound. The cost of the screening programme, including associated costs such as extra hospital admissions, was about US$ 250 per pregnancy.