Introduction: Using Identity and Social Identity Theory as frameworks, we investigated the contribution of placement in an Interprofessional Training Unit (ITU) on a maternity ward to professional and interprofessional identity development, the interplay between these identities, and the association with some background factors.

Methods: A prospective pre-post-intervention design was used. Before and after ITU placement, students in two Dutch hospitals participated in an online survey, comprising background characteristics, and scales measuring professional (PI) and interprofessional identity (IPI). PI and IPI scores between T0 and T1 were compared by means of a paired t-test. A two-way factorial ANOVA was used to test for differences between groups, based on background factors.

Results: Out of 209 students, 179 students (89.9%) completed the pre- and post-placement surveys. We found no significant change in professional identity formation, but a significant increase in interprofessional identity formation across the placement for students from all three professions, with midwifery students having the highest increase. Students with higher PI scores had significantly higher IPI scores before placement compared to students with lower PI scores, without a significantly higher increase in IPI during the placement. No significant differences in IPI change were found for other variables.

Discussion: We found that a one-week interprofessional placement significantly increased students’ interprofessional identity, with midwifery students showing the largest raise. Students with a higher PI also had a higher IPI before the ITU placement, suggesting a stronger PI is associated with a greater propensity for fostering IPI. Possible explanations for these findings are offered.