Attrition of participants over time poses a challenge in longitudinal research. This study aimed to explore how partner participation influenced maternal retention.

Using data from the P3 Cohort (a longitudinal pregnancy cohort), study retention was assessed at each stage of data collection up to 1 year postpartum. Participants were grouped according to their partner's level of participation in the study (participants who did not consent to the study team contacting their partners, participants whose partners were contacted but did not consent to participate, and participants whose partners actively participated). Cox proportional hazards models were used to evaluate the association between partner participation and participant attrition.

Of 2194 eligible participants, 38.9 % did not provide consent for the study team to contact their partner, and 42.1 % of partners that were contacted agreed to participate in the cohort. Retention rates in the cohort were high (97.5 % at 1 year postpartum) but varied by partner participation. Partner participation was associated with a significantly reduced hazard of attrition (HR=0.38, 95 % CI:0.15–0.92).

Active partner participation significantly enhances maternal participant retention. Inclusion of partners in pregnancy research may help reduce attrition and gain a more comprehensive understanding of family dynamics.

Attrition

Retention

Cohort study

Pregnancy

Fathers

© 2025 The Authors. Published by Elsevier Inc.