RSV Vaccine Guidance for Pregnant Women: Benefits, Safety, and Expert Advice

Transferred antibodies give infants vital defense against early-life respiratory illness.

By Medha deb

Created on Sep 23, 2025

Transferred antibodies give infants vital defense against early-life respiratory illness.

What Pregnant Women Should Know About the RSV Vaccine

Respiratory Syncytial Virus (RSV) is a common yet potentially severe viral infection, particularly harmful to infants and young children. The recent availability of the RSV vaccine for pregnant women has sparked questions regarding its safety, benefits, and timing. This in-depth guide synthesizes current expert guidance and evidence, addressing the most important concerns for expectant mothers.

Understanding RSV and Its Risks in Infants

RSV is a highly contagious respiratory virus that circulates primarily during the fall and winter months. Most children experience RSV by their second birthday, but for some—especially newborns and premature infants—the consequences can be serious.

Understanding the severity of RSV is crucial for parents, particularly during the RSV season. To better equip yourself with knowledge on how to recognize, treat, and prevent RSV in your children, explore our comprehensive guide on RSV symptoms, treatment, and prevention strategies. This resource ensures you're prepared and informed, safeguarding your little ones from this serious infection.

RSV can cause bronchiolitis and pneumonia in infants, potentially leading to hospitalizations.
Infants under six months of age are at especially high risk for severe illness and complications.
Each year in the U.S., RSV leads to 58,000–80,000 hospitalizations among children younger than five years, with most severe cases occurring in infants.
Premature babies, infants with chronic lung disease, and those with congenital heart conditions are particularly vulnerable.

How the New RSV Vaccine Works

The Pfizer RSV vaccine, marketed as Abrysvo, is designed for use in pregnancy to generate protective antibodies. These antibodies are transferred from mother to fetus, safeguarding the newborn against severe RSV infections during early life, when infants are most vulnerable.

While focusing on RSV, it's equally important to be aware of other childhood diseases that can pose risks. For thorough health protection, check out our in-depth insights on measles symptoms and vaccination, so you can ensure your child is well-protected from various infections during their formative years.

Mechanism: The vaccine prompts the mother’s immune system to produce RSV-specific antibodies, which cross the placenta into the baby’s bloodstream.
Longevity: Protection typically lasts for about six months after birth, offering critical defense during the highest-risk period.

The Importance of Getting Vaccinated During Pregnancy

The strongest benefit of the RSV vaccine for pregnant women is the direct protection it offers for newborns.

Newborns gain immune protection they otherwise wouldn’t have at birth, as their own immune systems aren’t mature enough to fight RSV effectively.
Vaccinating during pregnancy helps cut down the risk of severe RSV illness and hospitalizations in infants—especially in the first few months of life.
Some infants, such as those born preterm or with certain health conditions, are at the highest risk and may benefit most from the added protection.

Vaccination is just one part of ensuring your baby's health. It's also crucial to understand other viral infections that can impact infants. To gain further awareness on potential risks, read our complete guide on Fifth Disease, including its symptoms and prevention strategies. Staying informed can help you better protect your newborn.

Effectiveness of the RSV Vaccine in Pregnant Women

The effectiveness of the RSV vaccine for pregnant women has been demonstrated in multiple large studies.

In clinical trials, vaccination at 32 to 36 weeks of gestation resulted in:

Approximately 57% efficacy against lower respiratory tract illness caused by RSV in infants through six months of age.
Up to 82% efficacy at preventing severe, medically attended lower respiratory tract illness in infants up to three months old.
Up to 76.5% efficacy against severe RSV-LRTD (lower respiratory tract disease) for births in the 32–36 week vaccination window.

These results hold across diverse populations and are backed by both pre- and post-marketing surveillance.

Outcome	Vaccine Group	Placebo/Unvaccinated Group
Preterm Birth Rate	5.9%	6.7%
Severe LRTI Prevention (typical efficacy)	~70%	—
NICU Admissions, Jaundice, Sepsis	No increase	No increase

Is the RSV Vaccine Safe in Pregnancy?

Safety data for the RSV vaccine in pregnant women is robust and continually monitored by regulatory agencies.

Clinical trial data: No statistically significant increase in serious adverse events (SAEs) was noted between the vaccine and placebo groups for either mothers or infants.
A small, non-significant increase in preterm births was observed in early trials (especially at less than 32 weeks’ gestation). For this reason, the vaccine is now recommended only for use at 32–36 weeks gestation to avoid potential risks in earlier pregnancies.
A slight imbalance in hypertensive disorders of pregnancy (such as preeclampsia) was observed but was not conclusively linked to the vaccine. Ongoing studies are evaluating this potential association.
Post-licensure data (VAERS, V-safe, VSD) from the first season confirm no increase in risk of preterm birth or babies being born small for gestational age among vaccinated individuals in the recommended window.
Both the CDC and FDA continue to monitor the RSV vaccine’s maternal and infant safety profile, with post-marketing studies underway.

Who Should Receive the RSV Vaccine During Pregnancy?

The RSV vaccine is recommended for pregnant women and individuals between 32 and 36 weeks of gestation, typically administered during RSV season (fall and winter). The ideal window for vaccination ensures maximum protection for newborns while minimizing any risk of very early preterm birth.

Eligibility: Most healthy pregnant women between 32–36 weeks of pregnancy.
Timing: The single-dose vaccine is typically given during the third trimester, aiming for peak antibody transfer to the baby.
Prenatal providers can help determine the best timing based on current RSV circulation and personal pregnancy history.

Potential Side Effects and Risks

Reported side effects from the RSV vaccine in pregnant women are generally mild and similar to those seen with other vaccines.

Typical reactions: Arm soreness at the injection site, mild fatigue, mild headache, and low-grade fever.
Serious side effects remain rare. Clinical trial and real-world data continue to support a favorable risk-benefit profile when the vaccine is used within recommended gestational limits.

Balancing Benefits and Potential Risks

Based on available evidence, leading health authorities conclude the benefits of maternal immunization against RSV far outweigh any identified risks when used according to approved guidelines. Nevertheless, post-marketing studies are ongoing to monitor for:

Hypertensive disorders of pregnancy (such as preeclampsia)
Preterm birth in real-world settings
Rare or unexpected adverse events

Special populations or high-risk pregnancies may require individualized counseling.

Who Should NOT Get the RSV Vaccine During Pregnancy?

Not every pregnant woman is eligible for the RSV vaccine. Contraindications and specific considerations include:

Outside 32–36 weeks’ gestation: The vaccine is not recommended for individuals earlier than 32 weeks or later than 36 weeks pregnant.
History of severe allergic reaction: Individuals with known allergies to vaccine components should not receive this vaccine.
Those with unique obstetric or medical circumstances should consult their prenatal healthcare provider for individualized risk assessment.

Comparison: RSV Vaccine vs. Other Infant Protection Strategies

Protection Strategy	Who Gets It?	Main Benefit	Limitations
RSV Vaccine (Abrysvo, maternal)	Pregnant individuals (32–36 weeks)	Antibody transfer to baby, protects from birth	Limited to gestational window, ongoing safety monitoring
Monoclonal antibody (nirsevimab, infant shot)	Directly to newborns/infants	Protects high-risk infants or those born outside vaccination window	No maternal antibody transfer; must be given to baby postpartum

Advice from Leading Experts

Professional groups such as the CDC and ACOG (American College of Obstetricians and Gynecologists) support use of the RSV vaccine for eligible pregnant people during times of RSV circulation, stating:

Vaccination during pregnancy provides essential risk reduction for infants during their most vulnerable stage.
Prenatal discussions should cover vaccine benefits, any individual health history, and the optimal timing window.
For those giving birth outside RSV season or not within the eligible window, options like direct monoclonal antibody administration for the newborn may be considered.

Frequently Asked Questions

Is the RSV vaccine mandatory during pregnancy?
No. The vaccine is offered as an option to eligible pregnant individuals but is not required. Healthcare providers help weigh individual risk and preference in shared decision-making.
Does the vaccine protect mothers as well as babies?
The primary goal is to protect the infant by transferring maternal antibodies. Pregnant women are at risk for RSV, but they typically have milder symptoms; protection is mostly for the baby, not the mother.
Can the RSV vaccine be given alongside other pregnancy vaccines?
Yes. It can be administered with other recommended maternal vaccines (such as the Tdap and flu vaccine) but should be timed according to provider guidance for maximum safety and effectiveness.
What if I’m not eligible or miss the vaccine window?
For babies not protected by in utero vaccination (e.g., born before 32 weeks, delivered before vaccination, or outside RSV season), monoclonal antibody shots can offer individual protection post-birth.
Should I be concerned about new or evolving safety information?
Maternal RSV vaccination is under constant safety review. Current data strongly supports its safety and effectiveness in the recommended population, but all new reports are closely monitored.

Bottom Line: Should Pregnant Women Get the RSV Vaccine?

For most women and birthing individuals between 32 and 36 weeks of pregnancy during the RSV season, the vaccine offers a significant opportunity to protect their newborns from severe respiratory illness. Expert consensus underscores that when following current guidelines, the benefits of maternal RSV immunization outweigh any identified or theoretical risks.

Discussing your specific health situation, vaccination timing, and personal preferences with your obstetric care provider is the best way to make an informed decision that supports the health of both you and your baby.

References

Author

medha deb

Medha Deb is an editor with a master's degree in Applied Linguistics from the University of Hyderabad. She believes that her qualification has helped her develop a deep understanding of language and its application in various contexts.

Read full bio of medha deb