INTRODUCTION: Depression is the most common psychiatric morbidity in pregnancy, affecting more than 13% of pregnant women. Its diagnosis is based on the criteria established by the DSM-5 and the application of validated scales such as the Edinburgh Postnatal Depression Scale. However, there are still errors and shortcomings among healthcare professionals in the recognition, diagnosis and treatment of depression during pregnancy, with the resulting consequences and repercussions on the gestation itself or the foetus. OBJECTIVE: To present a review of depression in pregnancy, its risk factors, clinical characteristics, complications and treatment. METHODS: The PubMed and LILACS databases were used to search for manuscripts. Of the 223 articles found, 55 fulfilled the inclusion criteria. RESULTS: The prevalence of depression in pregnancy in South America is approximately 29% and the most significant risk factors are sexual abuse, pregnancy at an early age and intrafamily violence. Therefore, early diagnosis favours a reduction in risk behaviour, foetal neurodevelopmental disorders and obstetric outcomes. CONCLUSIONS: Depression in pregnancy is common condition but is underreported as its symptoms are often attributed to the pregnancy itself. The use of selective serotonin reuptake inhibitor antidepressants, particularly fluoxetine, which has not been associated with teratogenicity, is recommended, in addition to the implementation of non-pharmacological treatment such as psychotherapy, mindfulness and aerobic exercise. Educating healthcare professionals will facilitate the correct diagnosis and treatment of this condition.