Objective Maternal stress has been linked with higher risks of adverse pregnancy outcome. The authors investigated the association between maternal anxiety and depression scores in early pregnancy to birthweight and spontaneous preterm birth.

Methods The study cohort consisted of 3531 nulliparous low risk women who participated in the Screening for Pregnancy Endpoints study. Psychological state was assessed using the State-Trait Anxiety Inventory and the Edinburgh Postnatal Depression Scale. These hardcopy questionnaires were administered to the participant's at 15- and 20-week gestation. The authors compared the outcome measures in women with scores ≥90th centile to those in women with scores <90th centile. Linear and logistic models were used for data analysis adjusting for maternal smoking, body mass index, age, alcohol and ethnic origin.

Results There were 170 preterm births in the study cohort. Mean birth weight was 3374 g. Women who had the highest anxiety scores (≥90th centile) on the first visit had smaller babies (mean birthweight difference= −62 (−116, −7)) and a higher risk of preterm birth (OR 1.6 (1.0, 2.7)). Women who had the highest risk of depression score on the first visit had smaller babies (mean birthweight difference= −51 (−99, −3)) but their risk of spontaneous preterm birth was not increased.

Conclusion These results suggest that higher scores of anxiety and depression before 15-week gestation in pregnancy may be associated with reduced birth weight and a higher risk of spontaneous preterm birth.