Partner awareness and support for maternal RSV vaccination: a paired survey of pregnant women and co-residing partners in Japan.

Background

Maternal respiratory syncytial virus (RSV) vaccination was introduced into Japan's routine immunization program in April 2026. This study examined vaccine acceptance and household-level factors, including co-residing partner awareness and support, immediately before program introduction.

Methods

We conducted a nationwide web-based cross-sectional survey of pregnant women at 28-36 weeks of gestation and their co-residing partners from March 13 to 19, 2026. Paired data were obtained from 100 household pairs through the Rakuten Insight panel. The primary outcome was positive maternal RSV vaccine acceptance, defined as being vaccinated, planning vaccination, or intending vaccination. Associated factors were examined using logistic regression.

Results

Detailed awareness of the maternal RSV vaccine was higher among pregnant women than partners (66.0% vs. 22.0%). Among women with detailed awareness, 72.7% showed positive acceptance. Within-household agreement on detailed RSV and maternal RSV vaccine awareness was low (κ = 0.144 and κ = 0.220, respectively), with discordance mainly reflecting pregnant woman-only awareness. In multivariable analysis, partner support for vaccination (adjusted OR 11.17, 95% CI 3.66-34.07) and detailed partner awareness (adjusted OR 4.98, 95% CI 1.13-21.92) were independently associated with positive acceptance.

Conclusions

Partner support and awareness were independently associated with maternal RSV vaccine acceptance, although partner awareness was substantially lower than pregnant women's awareness. Implementation strategies should include co-residing partners as key participants in household decision-making.