Infections During Pregnancy

The vast majority of infections are harmless during pregnancy. However, a few can be passed on to the baby and cause harm. For some of these, we check your immunity with a simple blood test or take preventive measures; for others, for which there is no reliable test, the best way to protect yourself is by following a few hygiene measures. Here’s an overview—and what you can do yourself.

What We Test for Routinely

At the start of your pregnancy, we test your blood for several infections. We typically perform these serology tests once at the beginning and do not necessarily repeat them:

• HIV
• Syphilis (Lues)
• Hepatitis B
• Rubella (immunity)
• Chickenpox / Varicella (immunity)

Group B Streptococcus – the swab test shortly before delivery

About four weeks before your appointment, we’ll perform a simple swab test for Group B streptococci. These are bacteria that some women carry in their vagina or intestines without any symptoms—it’s not a disease, and it’s not something you’ve done wrong. They are harmless to you; only very rarely can they cause an infection in the baby during delivery. If we find Group B streptococci, prevention is simple: During delivery, you’ll receive an antibiotic through an IV that reliably protects the baby. That’s all you need to do.

What we don’t test for routinely, but will discuss with you

For the following infections, testing isn’t clearly recommended, and health insurance doesn’t cover it. Whether a test is worthwhile for you involves pros and cons that we’ll take the time to weigh together. This makes prevention all the more important:

Toxoplasmosis is caused by a parasite found primarily in raw meat and cat feces. A primary infection during pregnancy rarely harms the baby. In Switzerland, routine testing has not been performed for years because treatment does not reliably prevent transmission—which makes it all the more important that you prevent infection:

• Always cook meat thoroughly; avoid raw and air-dried sausage and meat products (e.g., salami, Mett, carpaccio, raw ham).
• Wash vegetables, fruits, and lettuce thoroughly; wash your hands after gardening or working with soil (gloves help).
• Have someone else clean the litter box daily—or, if it’s your turn, wear gloves and wash your hands afterward.

CMV (cytomegalovirus) is a widespread virus and harmless to healthy adults. However, if a woman is infected for the first time during pregnancy, it can occasionally harm the child, particularly the hearing. The main source of infection is young children, who shed the virus through saliva and urine. There is no routine test; if you’re at increased risk—for example, if you have a young child of your own or work in childcare—we’ll test for antibodies. Hand hygiene is the most effective measure:

• Wash your hands thoroughly after every diaper change and after contact with saliva, urine, or nasal secretions.
• Do not lick the child’s pacifier, spoon, or food; do not share glasses or toothbrushes.
• Kiss your child on the forehead or cheek instead of on the mouth.

Let’s be honest: With a toddler at home, it’s impossible to stick to these rules 100% of the time. Do what you can in your daily life—even that will significantly reduce your risk (SGGG 2021).

Parvovirus B19 (ringelröteln) is a common childhood illness; most adults are immune. If your child contracts the virus for the first time, it can rarely lead to anemia. The main source of infection is sick children—an issue particularly relevant for women with young children or those working in childcare. There is no vaccine; if you are not immune, avoid close contact with infected individuals. In the event of an outbreak in your community, we will check your immunity through a blood test and monitor the child via ultrasound if necessary.

When You Should Contact Us

Please contact us if you develop a fever, notice a rash, have flu-like symptoms, or have been in contact with someone who has fifth disease, chickenpox, or measles. We’ll then assess your immunity and take the appropriate measures if necessary. It’s better to ask once too often than not enough.

Vaccinations and More

Some infections can be prevented with vaccinations—such as whooping cough, the flu, or RSV (more → “Vaccinations”).