Can Hepatitis B affect pregnancy?

Hepatitis B is a liver infection caused by the Hepatitis B virus, a virus that targets liver cells and can cause both short-term (acute Hepatitis) and lifelong (chronic Hepatitis) illness. For many people, chronic infection sits quietly in the background without any obvious symptoms, sometimes for decades. That’s why pregnancy is such a crucial time to diagnose and manage it.

Globally, around 240 million people live with chronic Hepatitis B, and an estimated 71.4 million women of childbearing age are chronically infected. In the UK, about 1 in 200 adults has chronic HBV, with significantly higher rates in certain communities and in London compared to the rest of England.

The difference between acute and chronic matters. Acute Hepatitis B is a recent infection that many adults clear naturally. Chronic Hepatitis B means the virus’s surface antigen (HBsAg) persists in the blood for six months or more. Many women don’t know they carry the virus until routine antenatal screening picks it up.

Without intervention, babies infected at birth have over a high chance of developing chronic infection themselves, potentially leading to serious liver problems later in life.

Hepatitis B is transmitted through contact with infected blood and certain body fluids, not through everyday activities. You can’t catch it by sharing dishes, hugging, or sitting next to an infected person.

The main transmission routes relevant to pregnant women include:

• Unprotected sexual contact with an infected person
• Sharing needles, syringes, or unsterilised equipment
• Exposure to infected blood, including through historic infected blood incidents or medical procedures abroad in endemic countries
• From mother to baby at birth (vertical transmission)

In the UK, donated blood has been screened for Hepatitis B since the 1970s, so blood products are extremely safe today. However, if you’ve ever lived in, travelled to, or received medical care in a region with a higher prevalence of the virus, testing is strongly recommended. Contrary to some myths, you can’t get Hepatitis B from sharing cutlery, utensils, or from saliva.

However, there is one important mode of transmission that pregnant women need to keep in mind.

Vertical transmission is the passage of a virus from mother to baby. This almost always occurs at birth rather than during pregnancy. During labour and delivery, the baby is exposed to the mother’s blood and body fluids, giving the virus a chance to enter the baby’s bloodstream.

The risk of vertical transmission depends heavily on the types of antigens the mother has and her viral load (how much of the virus is in her blood).

• HBeAg status: The e antigen is a marker of active viral replication. HBeAg positive mothers face a transmission risk of 70–90% without any intervention.
• HBV DNA level: A high viral load is linked to increased risk. The transmission risk can be as high as 90% if the mother has a high viral load.

Why does this matter so much? Over 90% of infants develop chronic HBV without treatment if they’re infected at birth. Chronic infection in infancy can lead to cirrhosis and hepatocellular carcinoma decades later.

In the UK and many other countries, all pregnant people should be tested for Hepatitis B. Screening for Hepatitis B surface antigen should be performed in the first trimester for all pregnant women, typically at the booking appointment with a midwife. The screen detects HBsAg, the surface antigen that marks a current infection.

Modern newborn Hepatitis B vaccination is one of the most effective tools we have. When the first dose of the Hepatitis B vaccine is given within the first 24 hours of life, ideally within 12 hours, the protective efficacy is remarkable.

However, vaccination completion rates for infants born to HBV mothers are often suboptimal. As a parent, keeping track of your baby’s vaccination schedule through your GP and child health records is essential. If a dose is missed or delayed, contact your GP or child health clinic promptly.

A common concern for any HBV-infected mother is whether her delivery plan needs to change. The answer, in most cases, is no. Standard vaginal delivery doesn’t increase transmission risk compared to caesarean sections. Caesarean section is not routinely required purely because the mother has Hepatitis B.

During labour, medical teams follow standard infection control practices and ensure the baby receives its vaccine and promptly after birth. The key is planning: ensuring the healthcare team is aware of the maternal hepatitis B virus status before delivery.

Breastfeeding is safe for mothers with Hepatitis B if the baby has received vaccinations. Current evidence shows that Hepatitis B is not primarily spread through breast milk. Both the CDC and UK guidelines support breastfeeding once the baby has had the birth-dose vaccine, unless there are complications such as cracked, bleeding nipples.

Pregnancy changes your immune system, and after delivery, those changes can sometimes cause a temporary “postpartum flare.” This means a rise in liver enzymes and, occasionally, a spike in viral load. Postpartum care is essential for monitoring liver function in women with Hepatitis B as risks can increase during this period. Close monitoring by healthcare providers is crucial during pregnancy and postpartum for women with HBV.

Your follow-up plan after birth will typically include:

• Repeat liver function tests
• Viral load tests
• Review of whether antiviral therapy can be stopped safely or needs to continue
• Imaging assessment if there are signs of chronic liver disease

Long-term monitoring is important for all women with chronic HBV. Without regular check-ups, conditions such as cirrhosis and liver cancer can develop silently over years. Our blog on whether hepatitis B goes away on its own provides helpful context on the natural history of the virus and why ongoing care matters. Healthy lifestyle choices also support your liver: avoiding excess alcohol, maintaining a healthy weight, and attending regular medical reviews are all important.

Receiving a Hepatitis B diagnosis during pregnancy can bring a wave of emotions, from worry to guilt to uncertainty. These feelings are entirely normal, and it helps to know that many women live full, healthy lives with Hepatitis B and raise healthy families.

Protecting household contacts is straightforward:

• Partners and older children should be tested for Hepatitis B
• If they’re not immune, they should get vaccinated
• Safer sex practices are advised until a partner’s immune status is confirmed

What daily activities are safe?

Sharing meals, hugging, playing, and all normal family interactions don’t transmit Hepatitis B. Basic precautions include covering cuts, not sharing razors or toothbrushes.

The most effective way to protect future pregnancies is to prevent Hepatitis B infection in the first place. The Hepatitis B vaccine is safe, widely available, and highly effective.

Who should consider vaccination?

• Healthcare workers
• People with multiple sexual partners
• Partners of someone known to be infected
• People who inject drugs
• Travellers to endemic countries
• Anyone who simply wants extra protection

Can I have more children if I have chronic Hepatitis B?

Chronic Hepatitis B shouldn’t ward you off getting pregnant if that’s what you want to do. However, planning ahead with a liver specialist will help optimise your treatment and protect your baby. Viral load should be assessed before each pregnancy, and preventive steps-including HBV vaccination for the newborn and possible maternal antiviral therapy-should be planned from early in pregnancy.

Will Hepatitis B go away on its own after pregnancy?

Most adults clear acute Hepatitis B naturally, but pregnancy itself doesn’t cure Hepatitis B.

Is it safe to use fertility treatments or IVF if I have Hepatitis B?

Many individuals with Hepatitis B successfully use assisted reproduction. Fertility clinics routinely screen for Hepatitis B, coordinate antiviral treatment where needed, ensure partners are vaccinated, and follow strict infection control protocols. It’s important to get treated and undergo certain treatments to minimise the risk of transmission.

Do I need to tell my baby’s school or nursery that I have Hepatitis B?

Hepatitis B is not spread through casual contact in childcare settings, so routine disclosure is usually not required. Day-to-day activities such as meals, play, and cuddles are completely safe. Some parents choose to share medical information on a confidential basis with key staff, particularly to ensure proper handling of blood spills or accidents, but this is a personal decision.

What are the risks of chronic Hepatitis B?

Some studies show a slight association between chronic HBV and risks of gestational diabetes and preterm labour.

A Hepatitis B diagnosis in pregnancy can understandably cause worry, but modern medicine offers a powerful set of tools to protect both you and your baby. If you’re pregnant, planning a pregnancy, or simply unsure of your Hepatitis B status, take control of your health today by arranging a confidential test with Better2Know.