Health Services Research Centre, Akershus University Hospital, Lørenskog, Institute of Clinical Medicine, Campus Akershus University Hospital, University of Oslo, Lørenskog, Division of Mental Health, Norwegian Institute of Public Health, Oslo, Institute of Community Medicine, University of Tromsø, Tromsø, and Department of Gynecology and Obstetrics, Akershus University Hospital, Lørenskog, Norway.
Objective. To assess the association between maternal emotional distress in pregnancy and delivery of a small-for-gestational age offspring. Design. A cohort study in pregnancy. Setting. 50 hospitals with a maternity ward in Norway during 1998-2008. Population. 71 898 women with a singleton pregnancy in the Norwegian Mother and Child Cohort Study were followed from early pregnancy to delivery. Methods. Information on presence of emotional distress was obtained through self-administered questionnaires in pregnancy week 17 and 30 and on birthweight, gestational length at delivery and sex by linkage to the Medical Birth Registry of Norway. Emotional distress was measured by short-forms of the Hopkins Symptom Checklist-25. Main outcome measure. Small-for-gestational age offspring (birthweight