Depressive symptoms among pregnant and postpartum women are common. However, recent studies indicate that depressive symptoms in the perinatal period do not follow a uniform course, and investigations of the heterogeneity of time courses and associated factors are needed. The aim of this study was to explore whether depressive symptoms in the perinatal period could be categorized into several distinct trajectories of symptom development among subgroups of perinatal women, and to identify predictors of these trajectory groups. The study used data from 1,036 Norwegian women participating in a community-based prospective study from midpregnancy until 12-months postpartum. Depressive symptoms were assessed with the Edinburgh Postnatal Depression Scale at 7 time points (4 during pregnancy). Partner-related attachment, stress, childhood adversities, pregnancy-related anxiety, previous psychopathology, and socioeconomic conditions were assessed at enrollment. By means of growth mixture modeling based on piecewise growth curves, 4 classes of depressive symptom trajectories were identified, including (a) pregnancy only (4.4%); (b) postpartum only (2.2%); (c) moderate-persistent (10.5%); and (d) minimum symptoms (82.9%) classes. Multinomial logistic regression analyses showed that membership in the pregnancy only and postpartum only classes primarily was associated with pregnancy-related anxiety and previous psychopathology, respectively, whereas the moderate-persistent class was associated with diverse psychosocial adversity factors. Findings suggest heterogeneity in temporal patterns of elevated depressive mood, relating specific trajectories of time courses with distinct adversity factors. Researchers and clinicians should be aware of possible multiple courses of elevated perinatal depressive mood, and inquire about possible diverse adversity factors, aberrant pathways, and prognoses.