ObjectivesTo (1) compare changes in self-efficacy, social support, postpartum anxiety and postpartum depression in Canadian women collected before (Cohort 1) and during the COVID-19 pandemic (Cohort 2); (2) explore the women felt related to having a newborn during the pandemic; and (3) explore ways that women coped.MethodsPrior to the pandemic (October 1, 2019-January 1, 2020), an online survey was conducted with women had given birth within the past six months in one of the three Eastern Canadian Maritime provinces (Cohort 1). A second, similar survey was conducted between August 1, 2020 and October 31, 2020 (Cohort 2) during a period of provincial pandemic response to COVID-19.ResultsFor Cohort 1, 561 women completed the survey and 331 women in Cohort 2. Cohorts were similar in terms of age of women, parity, and age of newborn. There were no significant differences for self-efficacy, social support, postpartum anxiety, and depression between the cohorts. Difficulties that women reported as a result of COVID-19 restrictions included lack of support from family and friends, fear of COVID-19 exposure, feeling isolated and uncertain, negative impact on perinatal care experience, and hospital restrictions. Having support from partners and families, in-person/virtual support, as well as self-care and the low prevalence of COVID-19 during the summer of 2020 helped women cope.ConclusionWhile there was no significant difference in pre-pandemic and during pandemic psychosocial outcomes, there were still challenges and negative impacts that women identified. Consideration of vulnerable populations is important when making public health recommendations.What is already known on this subject?Previous work has shown the importance of social support in the postpartum transition in developing parenting self-efficacy and decreasing postpartum anxiety and depression. However, during the COVID-19 pandemic, women’s mental health, particularly during the perinatal period, has seen an increases in rates of postpartum anxiety and depression.What this study adds?This study is able to compare self-efficacy, social support, postpartum anxiety and depression between two cohorts of postpartum women living in Eastern Canada – pre-COVID-19 pandemic and during. While there was no significant difference in pre-pandemic and during pandemic psychosocial outcomes, there were still challenges and negative impacts that women identified.