Background: Pregnancy is a challenging time, and couples frequently experience psychological and sleep problems. Despite the dyadic effects of these problems, most interventions have focused on pregnant women alone, not on couples. The research team developed an innovative intervention targeting couples during pregnancy to fill the research gaps.

Objectives: (1) examine the effects of couple-based psycho-socio-educational intervention using WeChat/WhatsApp (WeLove) on dyadic psychological symptoms (depression, anxiety, stress symptoms), sleep quality, and life satisfaction with wearable data (stress, heart rate, and sleep quality) immediately after the intervention, with follow-up assessments at 3 months and 12 months after the intervention; and (2) examine the interdependence between psychological symptoms and sleep quality in pregnant women and their partners.

Methods: WeLove is a 6-week online intervention through WeChat/WhatsApp based on theoretical and evidence-based support. A three-arm double-blind randomized controlled trial will be used among 336 couples. Participants will be assigned to one of three groups and 112 couples per group: intervention 1 (couples for WeLove), intervention 2 (pregnant women for WeLove), or the control group (use WeChat/WhatsApp as normal). Participants will be assessed pre- and post-intervention, with follow-up assessments at 3 months and 12 months after the intervention. Generalized estimating equation analysis and thematic analysis will be performed to examine the research objectives.

Potential contributions: The findings will provide a cost-effective way to improve psychological and sleep outcomes in couples. Policymakers can use the study's results as evidence to consider an innovative intervention that aims to improve antenatal services in Hong Kong.