Abstract: ObjectiveTo describe mental health status in pregnant women and to estinate whether there is an association between psychosocial stress and low birthweight.MethodsA voluntary sample of 1 519 pregnant women who had the forcoming birth in a hospital in Hefei was selected.Their social demography and mental health infounanon were assessed by a questionnaire survey and were compared between women who delivered low birth weight neonates and women who deliverect nounal birth weight neonates.Chi square test relative risks and 95% confidence intervals were calculated by means of non-conditional Logistic regression.ResultsLow birth weight rates were different in different maternal registered peonanent residence, age and educational degree, and the differences were of significance(P<0.05 for all comparisons).There was no significant association between maternal anxiety and a low birth weight delivery, and the analysis of maternal depression, trait coping style, social support yielded the same results(P>0.05 for all comparisons).After adjusting formaternal social demogmphy and complicated disease factors, modemte or severe life events(odds ratio=3.619, 95% confidence interval: 1.863-7.028) was significantly associated with low birth weight delivery(P=0.000).ConclusionThis study provides evidence thatmoderate or severe psychosocial stress in pregnantwomenmay have adverse effect on fetal growth.