Vaccines for Pregnant Women: Which Ones You Need and When to Get Them

It is a busy time when you are pregnant. You are preparing for the baby and can't help but plan for all the newborn essentials, even if you're just 20 weeks pregnant. But don't forget that vaccines for pregnant women are also necessary to protect you and your baby from the moment they are born.

Role of Vaccination in Pregnancy

During pregnancy, your immune system adjusts in ways that make you more likely to catch certain infections, according to the Centers for Disease Control and Prevention.

Pregnancy makes you more vulnerable to infections like influenza, respiratory syncytial virus (RSV), and pertussis (whooping cough) complications.

A 2020 review in Frontiers in Immunology found that pregnancy also increases the severity of other types of infections, such as dengue fever and varicella-zoster virus (the virus that causes chickenpox and shingles).

By getting vaccinated, you create antibodies to fight off these diseases and give your baby early protection.

Recommended Vaccines for Pregnant Women

Your ob-gyn is the best person to advise you on which vaccines are necessary during pregnancy. They will take into account your immune system's health, any pre-existing medical conditions, and immunization history.

Below are some of the vaccines your healthcare provider may recommend before or during your pregnancy.

1. Tetanus, Diphtheria, and Pertussis (Tdap) vaccine

This combination vaccine helps prevent tetanus, diphtheria and pertussis during pregnancy. The pertussis component is essential for expectant mothers because newborns are vulnerable to severe complications.

When to get the Tdap vaccine: Dexter Ian L. Mallari, MD FPOGS, a Fellow of the Philippine Obstetrical & Gynecological Society, says one dose of Tdap vaccine is given between Week 27 and Week 36 of pregnancy.

The American College of Obstetricians and Gynecologists notes the Tdap vaccine can be safely administered at any point during pregnancy in special situations, such as when a vaccine is needed for wound treatment or during a pertussis outbreak.

2. Flu vaccine

For pregnant women, contracting influenza is serious and can lead to hospitalization, compared to those who are not pregnant.

Getting the flu vaccine during pregnancy can help protect the baby from the flu after birth, as the antibodies are passed along to the developing baby. Plus, breastfeeding women who get the flu shot can pass those antibodies to their babies through breast milk.

When to get the flu vaccine: You can get your flu shots any time during flu season, regardless of your trimester and as long as your doctor says it's okay. You can read more in Benefits of Flu Vaccine for the Whole Family.

3. Respiratory Syncytial Virus (RSV) vaccine

According to PIDSOG, babies under 6 months are two to eight times more likely to be hospitalized for RSV infection than for the flu.

The Philippine Infectious Disease Society for Obstetrics and Gynecology (PIDSOG) states that the RSV vaccine for pregnant women helps transfer antibodies to babies before birth, thereby protecting them from severe RSV disease, especially during their first six months of life.

In its latest position statement, PIDSOG says RSV is the leading cause of hospitalization among infants with cities like Baguio seeing the highest incidence of RSV in children aged 6 to 23 months.

When to get it: PIDSOG recommends the RSV vaccine from 28 weeks of pregnancy onward. Ideally, vaccination should occur more than two weeks before delivery for the transfer of antibodies to work. However, Dr. Mallari notes this vaccine is not always available, so talk to your ob-gyn about RSV vaccine early.

PIDSOG notes that the RSV vaccine can be given alongside Tdap, flu, or hepatitis B vaccines, as long as they're administered on different parts of the body and spaced at least two weeks apart.

4. Hepatitis B vaccine

Hepatitis B is a viral infection that affects the liver. Pregnant women can pass the virus to their babies during delivery because of the blood exchange that happens during childbirth. These babies can end up with a chronic infection, which means they have a higher chance of facing serious liver issues as they grow older.

WHO advises pregnant women to get tested for hepatitis B e-antigen (HBeAg). If positive, your doctor will plan based on your immune status. According to the Hepatitis B Foundation, many people with hepatitis B may remain unaware of their infection for decades because it often does not present with symptoms.

When to get the hepatitis B vaccine: If you haven't gotten the hepatitis B vaccine before pregnancy and you're at risk, talk to your ob-gyn.

Dr. Mallari says getting the hepatitis B vaccine during pregnancy is safe although it's not a priority and can be delayed postpartum. "It is usually recommended for pregnant women who are high risk of having hepatitis B, and those with chronic kidney and liver disease."

Remember, though, that even if you received the hepatitis B vaccine while you were pregnant, your little one still needs to get the hepatitis B vaccine after birth. The protective antibodies don't pass from mom to baby, so your baby must get vaccinated. Here's your baby's immunization schedule from birth to teen years.

FAQs About Vaccines for Pregnant Women

An ob-gyn will want to know immunization history before prescribing vaccines for pregnant women.

Below, Dr. Mallari helps clear up a few more common worries about vaccines during pregnancy.

Can a pregnant woman still get the flu or Tdap vaccine if she missed them or is unsure of her vaccine history?

Dr. Mallari says you can still get vaccinated, especially if the benefit of receiving the vaccine outweighs the risk. "As long as the vaccines being given are inactivated and within the right schedule, they are safe and beneficial for both the mother and the baby."

What are the possible side effects of vaccines given during pregnancy?

According to Dr. Mallari, common vaccine side effects include localized pain, swelling or redness at the injection site. Some may also experience headaches and nausea.

Dr. Mallari recommends a cold compress if you feel some muscle pain. You can also take paracetamol if you experience fever and chills, which is a normal response of the body.

"However, if you experience adverse reactions such as difficulty breathing, itchiness and appearance of rashes, consult a doctor immediately."

When should the MMR vaccine be taken?

Vaccination during pregnancy typically involves inactivated vaccines such as the four mentioned above. These use a killed version of the germ that causes the disease and are safe to be administered during pregnancy.

The MMR (measles, mumps, and rubella) vaccine or MMRV (mumps, measles, rubella, varicella) are live vaccines and are not given during pregnancy.

Dr. Mallari says, "If a non-pregnant woman received a live vaccine, like those mentioned, they are advised to have at least four-week interval prior to getting pregnant. Receiving these vaccines prior to getting pregnant are beneficial in preventing abnormalities to the fetus during pregnancy (e.g. Congenital Rubella Syndrome)."

If you have not been vaccinated or are unsure if you have received the MMR or MMRV vaccine as a child, consult your doctor if you're planning to become pregnant.

Clearing Up Misconceptions

Many misconceptions exist about vaccines, so Dr. Mallari encourages women who are planning to get pregnant or are already expecting to ask their doctors all their questions regarding vaccination.

One common misunderstanding is the idea that vaccines can harm the baby. According to Dr. Mallari, this usually comes from not knowing what's actually inside a vaccine or how each one is scheduled during pregnancy. 

For parents who worry about ingredients or testing, Dr. Mallari says vaccines for pregnant women use inactivated germs, so these shots can't cause the disease. 

"All vaccines before being available for use undergo a series of research, tests and clinical trials before being approved and deemed safe for public consumption."

Getting the right vaccines for pregnant women is one of the most effective ways to protect both you and your baby. Before getting vaccinated, consult your doctor about your immunization history and give your baby a healthy start before birth!

Join the Parenteam Moms and Dads Facebook group to see how fellow parents are finding their way through the pregnancy and parenting journey!