The longitudinal course of depressive symptoms during the perinatal period: A systematic review

Perinatal Depression (PND) is one of the most common complications (10-20 %) during the perinatal period and its clinical course and phenotypes are still an area of research. It is becoming increasingly clear that pregnant women and mothers with depression are not a homogeneous clinical group.A systematic literature search in 4 databases revealed 359 studies, 33 relevant studies met the inclusion criteria. We only included studies with at least three assessment points in total.Two to six trajectory classes were identified. A three trajectories solution was most observed. All the included studies reported a low symptom trajectory but ranged from 6.5 % to 92 %. The high-symptom group was in most of the studies the smallest subgroup (1.1 % - 14.6 %). Most of the studies described episodic trajectories of depressive symptoms during the peripartum. The most common risk factor associated with a high-symptom trajectory of depressive symptoms in our study was a history of depression. Important socio-demographic predictors were: young age, ethnicity, low maternal education, low income, single relationship status or relationship problems, unplanned or unintended pregnancy and experiencing high stress levels.The methodology and the observed PND trajectories of the included studies differed, which makes generalizability difficult in this review.PND is a frequent but heterogeneous disorder. Globally, four major groups could be distinguished: low, medium, high and episodic trajectories. There is a need for consensus regarding which assessment instruments to use, validated cutoff scores and similar time points of assessment.