[Psychosocial stress as a risk factor for preterm birth--first results of the BabyCare project]

Psychosocial stress is and has been under study in a plenty of epidemiological research done to further detect the mechanisms between risk factors and preterm birth, but the role of these possible risk factors is up to now not approved neither theoretically nor empirically. Associations calculated between those risk factors and preterm birth are highly inconsistent and with exceptions only moderate. Based on the data given by the BabyCare programme in a first analysis for the group of primiparae it will be analysed, which psychosocial risk factors are correlated with preterm birth and which of these can be judged as independent risk factors, as far as this can be ruled out by the sample-size given. The descriptive data analysis shows, that the frequency of psychosocial risk factors is varying as it can be expected by age and social stratification. The analytical analysis shows by the given sample-size that the variable "strong stress in the last 12 months before pregnancy" has the highest ODDS-Ratio, which is also almost significant. Unexpectedly there is no correlation between preterm birth and the frequency and characteristics of life-events in the last 12 months, nor between the stress index, nor between the frequency of psychosocial complaints. Weaker associations--further to be approved--are given with respect to work load and occupation, problems in partnership and emotional or social support as well as to unplanned pregnancy and "low social status". The risk-ratios of the psychosocial variables are altogether much lower than the ratios of the medical or behavioural risk factors. The analysis of preterm birth rates reveals, that "strong stress in the last 12 months before pregnancy" will especially raise the preterm birth rates of smokers by an additional factor of 1.5. The associations found have to be approved by raising sample-size by stratified analytical methods and additional research by follow-up or retrospective studies to finally find out the factors which arise in the subsequent time of pregnancy and might explain the higher risk of preterm birth in the group of women with "strong stress in the last 12 months before pregnancy".