the purpose of the current series of 3 investigations was to determine if mindfulness is a skill that may protect women’s mental health and wellbeing during pregnancy and the postpartum period. study 1 was a canada-wide cross-sectional investigation of 481 pregnant and 498 postpartum women. study 2 was a longitudinal follow-up of 150 pregnant women who participated in study 1. study 3 was a randomized-control trial of a community sample of 29 pregnant participants who were randomly assigned to either a brief mindfulness group (mg) or a comparison group (cg). participants in all 3 studies completed questionnaires assessing various mental health symptoms, wellbeing variables, and mindfulness engagement. in study 3, participants also provided feedback on their program experience. in both study 1 and 2, a negative association was observed between mindfulness engagement and several measures of mental health (stress, depression, anxiety, and obsessive-compulsive symptoms) and difficulties in mother-infant bonding, with moderate to large effect sizes. as well, a positive association was observed between mindfulness engagement and measures of wellbeing (resiliency and quality of life), as well as a measure of mania (study 1 only). in study 3, the results did not reveal statistically significant group differences on the mental health or wellbeing measures. however, it was found that both the mg and cg were well received by participants and that subjective impressions by participants in both groups were that the groups were beneficial for their wellbeing. combined, the results suggest that mindfulness may protect pregnant and postpartum women’s mental health and wellbeing. future research might examine the potential benefits of a lengthier perinatal mindfulness program in cultivating mindfulness skills and to better determine if an extended program may be helpful as a pro-active supportive intervention to protect maternal mental health and wellbeing during pregnancy and the postpartum period