We sought to evaluate the impact of the COVID-19 pandemic on perinatal outcomes while accounting for maternal depression or perceived stress and to describe COVID-specific stressors, including changes in prenatal care, across specific time periods of the pandemic. Data dyads from 41 cohorts from the National Institutes of Health Environmental influences on Child Health Outcomes Program (N=2983) were used to compare birth outcomes before and during the pandemic (n= 2355), and a partially overlapping sample (n=1490) responded to a COVID-19 questionnaire. Psychosocial stress was defined using prenatal screening for depression and perceived stress. Propensity-score matching and general estimating equations with robust variance estimation were used to estimate the pandemic’s effect on birth outcomes. Symptoms of depression and perceived stress during pregnancy were similar prior to and during the pandemic, with nearly 40% of participants reporting mild to severe stress, and 24% reporting mild depression to severe depression. Gestations were shorter during the pandemic (B=-0.33 weeks, p=0.025), and depression was significantly associated with shortened gestation (B=-0.02 weeks, p=0.015) after adjustment. Birth weights were similar (B=-28.14 g, p=0.568), but infants born during the pandemic had slightly larger birth weights for gestational age at delivery than those born before the pandemic (B=0.15 z-score units, p=0.041). More women who gave birth early in the pandemic reported being moderately or extremely distressed about changes to their prenatal care and delivery (45%) compared with those who delivered later in the pandemic. A majority (72%) reported somewhat to extremely negative views of COVID-19 on their life. In this national cohort, we detected no effect of COVID-19 on prenatal depression or perceived stress. However, experiencing the COVID-19 pandemic in pregnancy was associated with decreases in gestational age at birth as well as distress about changes in prenatal care early in the pandemic.