This post-marketing study is a multicenter cohort study in pregnant women vaccinated with Abrysvo (RSV vaccine）designed to confirm the safety in pregnant women and their infants under actual clinical practice in Japan.

Inclusion Criteria:

1. Pregnant women who have been vaccinated with Abrysvo for the first time after Abrysvo is launched. Pregnant women who have previously participated in the clinical trials of Abrysvo will be excluded.
2. Vaccinated participants who have provided written consent regarding their participation in the study and entry of symptoms to ePRO with the use of their devices (smartphones, tablets PC, etc.) (or paper-PRO if there is any compelling reason) upon understanding the explanatory document. For a minor vaccinated participant, the parent(s) or legally acceptable representatives shall provide written consent.
3. Pregnant women who have provided written consent to the participation of their infants in the study. For a minor vaccinated participant, the parent(s) or legally acceptable representatives shall provide written consent.

Exclusion Criteria:

• There are no exclusion criteria for this study.

Pregnant women who have been vaccinated with Abrysvo for the first time and their infants.

Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical\_trials/trial\_data\_and\_results/data\_requests.