5 Most Common Prenatal Infections Every Expecting Mother Should Know

Pregnancy is an exciting journey, but it also requires careful attention to health. One important part of prenatal care is screening for infections that can be passed from mother to baby during pregnancy, childbirth, or shortly after birth.

In Indonesia, several prenatal infections are closely monitored because of their high prevalence and risk of vertical transmission. Many of these infections do not cause noticeable symptoms in pregnant women.

As a result, infections may go undetected without routine testing. According to screening data and prevalence studies in Indonesia, five infections stand out as the most common among pregnant women in Indonesia.

Understanding these infections, how common they are, and why early screening matters can help expecting mothers make informed decisions for a healthier pregnancy.

1. Hepatitis B (Most Common)

Hepatitis B is the most common prenatal infection in Indonesia, with national screening data showing a prevalence of approximately 1.5% to 2.5% among pregnant women. In some regions, hundreds of cases are identified each year through routine antenatal screening.

Hepatitis B affects the liver and often shows no symptoms. During pregnancy, the main concern is transmission from mother to baby during delivery.

Babies infected at birth have a high risk of developing chronic hepatitis B, which can lead to serious liver disease later in life. Early screening during pregnancy allows doctors to manage the condition properly and ensure newborns receive immediate protection.

In addition, Hepatitis B vaccination before pregnancy is strongly recommended for women who are not yet immune, as it is one of the most effective ways to prevent infection and transmission.

2. Syphilis

Syphilis is the second most concerning prenatal infection based on national case numbers. Recent data estimates tens of thousands of pregnant women are affected annually, with more than 23,000 positive cases reported in a single year.

Ongoing surveillance suggests continued transmission among women of reproductive age. Syphilis can have severe consequences if left untreated, including miscarriage, stillbirth, premature birth, or congenital syphilis.

Babies born with congenital syphilis may suffer from physical deformities, organ damage, or developmental delays. The infection is easily detected through a blood test and can be treated effectively with antibiotics during pregnancy.

Early diagnosis is critical to prevent complications.

3. Human Immunodeficiency Virus (HIV)

HIV (Human Immunodeficiency Virus) affects an estimated 0.3% to 0.7% of pregnant women in Indonesia. While the percentage is lower than hepatitis B or syphilis, HIV remains a national priority due to its long-term health impact.

Without treatment, HIV can be passed from mother to baby during pregnancy, delivery, or breastfeeding. With early detection and proper antiretroviral therapy, the risk of transmission can be reduced to very low levels.

This is why STD screening (including Hepatitis B, Syphilis, HIV, etc.) before marriage is highly encouraged. Early screening allows couples to address health concerns early and plan for safer pregnancies in the future.

4. Toxoplasmosis

Toxoplasmosis is part of the TORCH group of infections and shows high exposure rates in local studies. Research conducted in several regions of Indonesia reports toxoplasmosis prevalence of up to 55% among women, indicating widespread exposure.

Although many infected adults experience no symptoms, toxoplasmosis during pregnancy can lead to miscarriage or serious fetal complications, including:

• Vision problems
• Neurological damage
• Developmental delays

Because exposure is common and often unnoticed, prenatal screening and lifestyle guidance, such as avoiding raw meat and practicing good hygiene, are essential for reducing risks during pregnancy.

5. Rubella

Rubella, also known as German measles, is part of the TORCH group of infections. Studies show rubella exposure rates as high as 59% in some populations, although not all women have protective immunity.

Rubella infection during early pregnancy can cause Congenital Rubella Syndrome, which may lead to heart defects, hearing loss, vision problems, and developmental delays. The highest risk occurs during the first trimester.

For this reason, Measles-Mumps-Rubella (MMR) vaccination before pregnancy is strongly recommended for women who are not immune. Knowing your immunity status before conception helps protect future pregnancies.

Why Prenatal Screening Matters in Indonesia

In Indonesia, hepatitis B, syphilis, and HIV are prioritized under the national Triple Elimination Program due to their high screened case numbers and serious outcomes for newborns. Toxoplasmosis and rubella complete the list of most common prenatal infections based on prevalence studies and clinical findings.

Because many of these infections show no early symptoms, routine antenatal screening remains the most reliable way to protect mothers and babies. Early detection allows healthcare providers to:

• Prevent mother-to-child transmission
• Reduce pregnancy and delivery complications
• Support healthy fetal development
• Provide clear and personalized care plans

If you have questions about prenatal infection screening or test results, you are welcome to contact us for professional medical guidance.

FAQ: Prenatal Infections Explained

What is a prenatal infection?

A prenatal infection happens when a pregnant woman has an infection that can be passed to her baby during pregnancy, childbirth, or shortly after birth. These infections are caused by viruses, bacteria, or parasites and may spread through the placenta, the mother’s bloodstream, or the birth canal.

Many women do not notice symptoms, which is why regular prenatal screening is essential.

How can infections affect pregnancy?

Prenatal infections can increase the risk of miscarriage, premature birth, or low birth weight. Some infections may cause birth defects, hearing or vision problems, or long-term developmental delays.

Early diagnosis and treatment greatly reduce these risks.

Are prenatal infections common in Indonesia?

Yes. Based on screening data in Indonesia, infections such as hepatitis B (1.5-2.5%), syphilis, HIV (0.3-0.7%), toxoplasmosis (up to 55%), and rubella (up to 59%) are commonly identified among pregnant women.

Can prenatal infections be prevented?

Many prenatal infections can be prevented or managed through routine prenatal checkups, blood tests, vaccinations, good hygiene, safe sexual practices, and avoiding raw or undercooked foods. Early screening allows timely treatment and better pregnancy outcomes.

Prenatal Care You Can Trust at Bali International Hospital

At our international hospital, we provide comprehensive prenatal screening and maternal care based on international medical standards. Our experienced obstetric team supports expecting mothers from early pregnancy through delivery with personalized and compassionate care.

We encourage all expecting mothers to book an appointment early to ensure timely screening, early intervention, and peace of mind throughout pregnancy. Proactive care today helps protect your baby’s health for a lifetime.