Infertility is a global public health issue, affecting approximately 15% of childbearing-aged couples around the world. It is often a challenging dyadic life experience that generates adverse impacts on the psychosocial well-being of couples at childbearing age. Numerous psychosocial interventions have been developed for infertile women, and their efficacy and effectiveness were supported empirically. This study attempts to address the limitations incurred in existing psychosocial interventions for infertility by: (1) including infertile men and couples who have not sought fertility treatment and (2) incorporating relational outcomes within psychosocial interventions for infertile couples. This is a two-arm, with equal randomization, parallel randomized controlled trial. It compares the efficacy of a couple-based Integrative Body-Mind-Spirit (I-BMS) group intervention to a waitlist control group in improving dyadic couple flourishing and fertility-related quality of life among couples who are diagnosed of infertility in Hong Kong. It also aims to investigate the dyadic associations between infertile husbands' and wives' baseline primary outcomes and changes in primary outcomes following the intervention.

On hundred and seventy-eight infertile couples will be recruited through hospitals, clinics and local communities in Hong Kong. Each prospective couple will complete an online screening survey. Eligible couples will complete the baseline assessment, and then be randomized in a ratio of 1:1 into one of the two arms. Arm 1 is the couple-based I-BMS intervention for infertility, which consists of four 3-hour sessions within one month. Arm 2 is the waitlist control. Randomization will be performed by a computer. All eligible couples will be contacted by a research assistant for a pre-group interview prior to the commencement of the I-BMS intervention. The primary outcomes are changes over the measurement points in dyadic couple flourishing and fertility quality of life. The secondary outcomes include changes over the measurement points in empathy towards partner, partnership, relationship satisfaction, anxiety, depression, infertility-related blame, and resilience. Assessments are administered at baseline, post-intervention, 1-month follow-up, and 5-year follow-up. Structural equation modelling will be employed to examine the efficacy of the couple-based I-BMS intervention based on the intention-to-treat principle, as well as the dyadic association between infertile husbands' and wives' primary outcomes.

Eight hypotheses are generated. First, it is hypothesized that, after controlling for baseline dyadic couple flourishing, couples in the I-BMS intervention group will report significantly higher dyadic couple flourishing than their counterparts in the waitlist control group following the intervention. Second, it is hypothesized that, after controlling for post-intervention dyadic couple flourishing, couples in the I-BMS intervention group will report significantly higher dyadic couple flourishing than their counterparts in the waitlist control group at one-month follow-up. Third, it is hypothesized that, after controlling for baseline dyadic fertility quality of life, couples in the I-BMS intervention group will report significantly higher dyadic fertility quality of life than their counterparts in the waitlist control group following the intervention. Fourth, it is hypothesized that, after controlling for post-intervention dyadic fertility quality of life, couples in the I-BMS intervention group will report significantly higher dyadic fertility quality of life than their counterparts in the waitlist control group at one-month follow-up. Fifth, it is hypothesized that wives' baseline fertility quality of life is predicted by their own and their husbands' baseline couple flourishing. Sixth, it is hypothesized that husbands' baseline fertility quality of life is predicted by their own and their wives' baseline couple flourishing. Seventh, it is hypothesized that wives' post-intervention improvements in fertility quality of life is predicted by their own and their husbands' post-intervention improvements in couple flourishing. Eighth, it is hypothesized that husbands' post-intervention improvements in fertility quality of life is predicted by their own and their wives' post-intervention improvements in couple flourishing.