Introduction: The presence of depression can difficulties the interpersonal relationships of the pregnant woman, related to the formation of affective bonds with the fetus and in the adaptation to the new routine and social role after the baby's birth. In addition, there is no consensus about the negative impacts of pregnancy depression on obstetric parameters and perinatal outcomes. Some studies report that the presence of depressive symptomatology in pregnancy may be associated with increased risk for preeclampsia, prematurity, low birth weight, and lower Apgar score. Other studies, however, found no association between pregnancy depression and unfavorable perinatal outcomes. Objective: The objectives of this study were to identify the prevalence of depression among pregnant considering sociodemographic and healthy data, to identify the factors associated with depression in the gestational period and to evaluate the association between depression and perinatal outcomes. Methods: A cross-sectional retrospective study was performed evaluating 628 protocols from 2002 to 2016, routinely used in Psychological service of ambulatory of Obstetric Clinic of HC-FMUSP/ Ambulatory Psychology Department of the Clinical Obstetrics Division of the Hospital das Clínicas of the Faculty of Medicine of the University of São Paulo and evaluated the presence of depression using the tool PRIME-MD. For the comparison of the groups of patients with and without depression in relation to quantitative variables, the Student's ttest or the non-parametric Mann-Whitney test was used, depending on the distribution of the variable of interest. In order to evaluate the association between two qualitative variables, Pearson's Chi-square test or Fisher's exact test, when appropriate, was considered. Linear regression models and logistic regression models were adjusted to assess whether the depression group was consistently significant in the presence of other covariates. Results: the prevalence of depression was 22.1% (n = 139). The mean age in the group with depression was 29.60 years (SD = 6.60) and 29.64 years (SD = 6.66) in the group without depression. Among the variants of characterization, considering the per capita family income, the women with lower income have significantly higher depression than the higher income ones (p=0,012). When considering the perinatal outcome variables, the newborn weight and the Apgar score <7 at the 1st minute were lower in the depression group, with a significant difference between the groups, respectively (p=0.005) and (p=0.002).The linear regression model was adjusted for the newborn weight and logistic regression model was adjusted for the Apgar 1 minute <7to verify the consistency of the association between the presence of depression and the variables of characterization and perinatal outcomes with a statistically significant difference. In both cases, the diagnosis of depression was associated with lower birth weight (p=0.021) and Apgar of 1 minute <7 (p<0.001). Conclusion: Depression, in addition to e...