RSV Vaccine in Pregnancy 2026: Free in Yokohama | Timing, Effectiveness & Side Effects
- 5 days ago
- 2 min read
Conclusion
Starting April 2026, the RSV vaccine for pregnant women has become free in Yokohama.The recommended timing is 28–36 weeks of pregnancy, and the vaccine helps protect newborns from severe respiratory infections.
What is RSV?
RSV (Respiratory Syncytial Virus) is a common virus that can cause serious lung infections in infants, including pneumonia and bronchiolitis.
Almost all children are infected by age 2, but newborns are at highest risk of severe illness.
② ワクチンの仕組み（母子免疫）
How does the RSV vaccine work?
The RSV vaccine faccine for pregnaor pregnant women is a maternal immunization vaccine.
When the mother is vaccinated:
Antibodies are produced in her body
These antibodies pass through the placenta
The baby is protected immediately after birth
新生児の肺炎などを防ぐ効果がある
Effectiveness of the RSV vaccine
The vaccine provides strong protection for newborns:
About 50–60% reduction in RSV infection requiring medical care
About 70–80% reduction in severe cases (hospitalization level)
In clinical studies, severe RSV infection was reduced by up to 80% in early infancy
③ 接種タイミング
6
When should pregnant women get the RSV vaccine?
The recommended timing is:
28 weeks to 36 weeks of pregnancy
💡 特に重要ポイント
早すぎると効果が弱い
出産直前だと抗体が十分に移行しない
30〜32週が実臨床ではよく推奨される
Cost in Yokohama (2026 update)
From April 2026 → Free (public vaccination program)
Before 2026 → 約3〜4万円の自己負担
👉 定期接種化により実質“無料化”
④ 副反応
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Side effects of the RSV vaccine
Most side effects are mild to moderate:
Injection site pain, redness, swelling (~40%)
Fatigue, headache, muscle pain (~20–30%)
Serious side effects are rare, and no increase in birth complications has been reported.
Is the RSV vaccine safe?
Current evidence shows:
No increase in birth defects
No increase in newborn complications
Strong safety profile
However, patients with pregnancy-related conditions (e.g., hypertension) should consult their doctor.
Why this vaccine is important
RSV infection in newborns can lead to:
Bronchiolitis
Pneumonia
Hospitalization
The RSV vaccine is one of the first effective ways to protect newborns immediately after birth.
Doctor’s perspective
The RSV vaccine represents a major shift in preventive medicine.
Instead of treating illness after birth, we can now protect babies before they are even born.
For many patients, this is one of the most impactful preventive interventions available during pregnancy.
Summary
RSV vaccine became free in Yokohama in 2026
Recommended timing: 28–36 weeks
Prevents severe infection by 70–80%
Side effects are generally mild
Clinic Information
THE YOKOHAMA FRONT CLINIC MALLYokohama, Japan
We provide vaccination and consultation for pregnant women.International patients are welcome.
Medical Park Direct Tower Yokohama is a specialized clinic focused on fertility treatment, gynecology, and women’s healthcare.
Located just a few minutes from Yokohama Station, the clinic provides a comfortable and accessible environment for patients seeking professional medical support.
Our clinic is designed specifically for women, and most consultations are conducted by female physicians, ensuring a safe and reassuring experience.
