An emerging body of literature suggests there is a relationship between a pregnant woman’s psychological wellbeing and the development of maternal-fetal attachment (MFA) and early postpartum bonding. The nature of this relationship is not well understood because of the limited theoretical framework surrounding the construct of MFA and variations in study methods and data collection points. In this systematic review, we synthesize the published literature to determine the nature of the relationship from the antenatal to early postnatal period and to provide recommendations for future research and clinical practice. Using the preferred reporting items for systematic reviews and meta-analyses (PRISMA) approach, four electronic databases were searched for peer-reviewed empirical studies, published in English. Articles were considered for inclusion if data was collected on at least one domain of maternal wellbeing/mental health and MFA during pregnancy or MFA during pregnancy and the mother-infant relationship during the early postpartum period (up to 12 weeks). No date parameters were applied to the search strategy. The review was registered with PROPSERO (registration number: CRD42018096174). 25 studies examining maternal mental health and MFA/postpartum bonding were selected for inclusion in this review. Key findings identified from the review were: a need to validate existing mental health measures or develop new measures specific for use in antenatal populations; inconsistencies in data collection points throughout pregnancy and postpartum; a lack of consensus about the construct of MFA and the way it is assessed; and a continued focus on postpartum outcomes. Scientific gaps remain in our understanding of the relationship between maternal mental health and both MFA and postpartum bonding which limit our theoretical understanding of the MFA construct. Recommendations for future research are to employ prospective longitudinal designs that span the full pregnancy and postpartum period, and for consistency in the terminology and methodology used when considering MFA. A re-focus of research attention on the theory behind MFA will allow a richer and more holistic account of the emerging relationship between mother and baby.

Experience plays a crucial role in the development of the face processing system. At 6 months of age infants can discriminate individual faces from their own and other races. By 9 months of age this ability to process other-race faces is typically lost, due to minimal experience with other-race faces, and vast exposure to own-race faces, for which infants come to manifest expertise [1]. This is known as the Other Race Effect. In the current study, we demonstrate that exposing Caucasian infants to Chinese faces through perceptual training via picture books for a total of one hour between 6 and 9 months allows Caucasian infants to maintain the ability to discriminate Chinese faces at 9 months of age. The development of the processing of face race can be modified by training, highlighting the importance of early experience in shaping the face representation.

Significance: The potential benefits of infant sleep for memory processing are largely unexplored. Here we show evidence that having an extended nap (≥30 min) within 4 h of learning helps 6- and 12-month-old infants to retain their memories for new behaviors across a 4- and 24-h delay. These results suggest that infants rely on frequent naps for the formation of long-term memories.