Trajectories of depressive symptoms among mothers of preterm and full-term infants in a national sample.

To examine postpartum depressive symptom trajectories from birth to age 5 and their risk factors in a national sample of mothers of preterm and full-term infants. The racially and ethnically diverse sample comprised 11,320 maternal participants (Mage = 29; SD = 5.9) in the Environmental influences on Child Health Outcomes (ECHO) Program in the USA with data on newborn gestational age at birth (≥ 22 weeks) and maternal depression symptoms during the first 5 years following childbirth. Growth mixture models determined the number and trajectory of postpartum depression classes among women in the preterm and full-term groups, and we examined predictors of class membership. Five trajectories described depressive symptoms for both groups; however, notable differences were observed. One in 5 mothers of preterm infants developed clinically relevant depressive symptoms over time compared with 1 in 10 mothers of full-term infants. Among women who delivered preterm compared with those who delivered full-term, symptoms were more likely to increase over time and become severe when offspring were older. Distinct subgroups describe mothers' depressive symptom trajectories through 5 years following childbirth. Mild to moderate depressive symptoms may onset or persist for many women beyond the initial postpartum period regardless of newborn gestational age at birth. For women with preterm infants, initially mild symptoms may increase to high levels of severity during the preschool and toddler years.