DO STRESSFUL LIFE EVENTS AFFECT DURATION OF GESTATION AND RISK OF PRETERM DELIVERY

The present study was designed to test the relation between stressful life events experienced during pregnancy and the risk of preterm deliv ery and shortened duration of pregnancy. We collected data prospective ly in a general population sample, including repeated questionnaire me asures of exposure to stressful life events during pregnancy. Between August 1989 and September 1991, 8,719 Danish-speaking women with singl eton pregnancies attended antenatal care. Of these women, 5,873 (67%) completed all questionnaires. When indicating an event, the woman was asked to rate the amount of stress induced by this event. Measurement of gestational duration was primarily based on early ultrasound scan. When we evaluated life events independently of the individual's apprai sal, we found no association with duration of gestation or risk of pre term delivery. In contrast, life events assessed by the subject as hig hly stressful were associated with shorter mean duration of gestation and increased risk of preterm delivery. This association was observed primarily with events experienced between the 16th and 30th week of ge station. Women who had one or more highly stressful life events had a risk of preterm delivery 1.76 times greater than those without stressf ul events (95% confidence interval = 1.15-2.71). We found no evidence for a buffering effect of social support.