Heterogeneity in perinatal depression: A systematic review of network analyses

Perinatal depression, a common mental disorder that affects up to 34% of mothers, has been shown to be highly heterogeneous, with mothers differing substantially in experienced symptoms and trajectories. In recent years, the use of network analyses in perinatal depression has grown rapidly, which calls for a systematic analysis of studies published so far. Following PRISMA guidelines, we conducted a systematic review of studies performing network analyses to investigate symptoms of pre- and postpartum depression. A total of 15 studies were included for review, comprising 44 distinct networks, of which 24 networks analyzed symptoms in the prenatal phase and 20 in the postpartum phase. Comparative analysis of strength centrality ranking on a subset of 15 networks (7 prenatal; 8 postpartum) identified mood as the most central symptom. When comparing the ranking of symptoms overall (considering all networks, pre- and postpartum) with the ranking based on prenatal networks only, only minor differences were observed (the two symptom pairs fatigue-worthlessness and suicidal ideation-appetite switched ranking positions). In contrast, larger differences were observed when comparing the ranking of symptoms overall (considering both pre- and postpartum networks) with the ranking based on postpartum networks only. Most interestingly, the symptom sleep emerged as a more central node in postpartum networks, while psychomotor symptoms decreased in importance. Our findings highlight differences in the symptom structure of perinatal depression across different phases of pregnancy and may inform symptom-focused prevention and intervention efforts.