Understanding the hepatitis B vaccine for newborns

As you prepare to welcome your baby, it’s natural to have questions about what happens after birth. Your care team is there to support you and help you make informed choices, including steps that can help protect your newborn early on. One of those steps is the hepatitis B vaccine, which is recommended within the first 24 hours after birth.

This early protection can help reduce the risk of a serious liver infection that may lead to long-term health problems.

What is hepatitis B?

Hepatitis B is a virus that affects the liver. It can cause a short-term illness, but in many cases — especially in infants — it becomes a long-lasting infection.

Chronic hepatitis B can lead to serious health issues later in life, including:

• Liver cancer
• Liver failure
• Scarring of the liver, called cirrhosis

Infants and young children are much more likely than adults to develop lifelong infection if they are exposed.

Why the vaccine is given at birth

Giving the hepatitis B vaccine shortly after birth helps protect babies during a time when they are most vulnerable.

Newborns who become infected have a high risk of developing lifelong infection. Starting the vaccine at birth helps reduce the chance of infection before the full vaccine series is complete.

Health organizations, including the CDC and the American Academy of Pediatrics, recommend that newborns receive their first dose within 24 hours, whenever possible.

How hepatitis B spreads

Hepatitis B spreads through contact with infected blood and bodily fluids.

For newborns, exposure can happen during the birth process if the virus is present in the birthing parent’s blood or fluids. However, exposure isn’t limited to birth.

The virus can also be present in saliva and tears and can survive on surfaces for up to a week. This means babies may be exposed through close contact with others, even when no one knows they carry the virus.

Why vaccination is recommended for all newborns

Even if you don’t have hepatitis B or believe your baby’s risk is low, vaccination is still recommended.

Many people who carry the virus don’t know they have it. Because of this, it’s possible for a newborn to be exposed through everyday contact with family members, caregivers or others.

Vaccinating at birth helps provide protection right away, before any unexpected exposure can occur.

How effective the vaccine is

The hepatitis B vaccine is highly effective.

The first dose given at birth provides strong early protection. After completing the full vaccine series, protection increases even further.

Widespread use of the vaccine in the U.S. has led to a dramatic decline in new infections among infants and children.

Is the hepatitis B vaccine safe?

Yes. The hepatitis B vaccine has been used for decades and has been extensively studied.

It is considered safe for newborns, infants and children. No safety concerns have emerged from long-term use.

According to Jeffrey Silvers, M.D., medical director of pharmacy and infection control at Sutter, “A small jab at birth with a very safe, well-studied vaccine causes insignificant pain to your new baby compared to the suffering that will occur if they develop hepatitis B.” 

Why timing matters

Delaying the first dose leaves a window when your newborn may be at risk.

There’s no evidence that waiting until 2 months provides added benefit. Receiving the vaccine at birth helps protect your baby during the earliest and most vulnerable stage. 

Can hepatitis B be treated?

There is currently no cure for hepatitis B.

While treatment can help manage the condition, it does not eliminate the virus. Preventing infection through vaccination is the most effective way to protect long-term health. 

How common is hepatitis B?

Hepatitis B remains a concern in the United States.

Millions of people are living with chronic infection, and thousands of new cases occur each year. Many of these infections can be prevented through vaccination.

A reassuring step for your baby’s health

Welcoming a new baby comes with many decisions. Learning about recommended vaccines, like the hepatitis B vaccine, can help you feel more prepared for those early moments.

If you have questions, your care team can talk through what to expect and help you make the choice that feels right for your family.