The information provided below is for readers based in the United States of America. Readers outside of the United States of America should seek the information from local sources.

Description: What is the meningococcal vaccine?

The meningococcal vaccine is a shot that is administered to train the immune system to recognize and defend against a bacterial species called Neisseria meningitides, often called meningococcus. There are several strains of N. meningitides that cause disease, and there are different types of meningococcal vaccine. In the United States, three types of meningococcal vaccine are available currently. Two of the types –one called the tetravalent meningococcal conjugate vaccine (MCV4), the other called tetravalent polysaccharide vaccine (MPSV4) – each teach the immune system to recognize four strains of N. meningitides, known as the A, C, W, and Y serogroups. The third type of meningococcal vaccine, called MenB vaccine, is for teaching the immune system to recognize another strain of N. meningitides called serogroup B. In some cases, more than one company manufactures a particular type of N. meningitides vaccine.

What is meningococcal vaccine given to prevent or treat?

A meningococcal vaccine is administered to prevent meningococcal disease. Caused by N. meningitides, often called meningicoccus, meningococcal disease can take the form of meningitis (inflammation of the layers of tissue between the brain and skull) and/or sepsis (infection throughout the body). The need for either a vaccine against ACWY or B N. meningitides depends one’s age, occupation, and environment. At the time of the writing of this report (November 2017), for example, outbreaks of serogroup B meningococcal disease are occurring at the University of Massachusetts at Amherst, and at Oregon State University in Corvallis, so there are efforts in both of those locations to immunize students specifically with MenB vaccines.

How does meningococcal vaccine work?

Meningococcal vaccines contain proteins that also are present on the outside of N. meningitides bacterial cells. ACWY vaccines contain proteins that are particular to N. meningitides strains A, C, W, and Y, whereas MenB vaccines contain a protein that is particular to N. meningitides serogroup B. Since there are no live bacterial cells in the vaccine, you cannot get an N. meningitides infection from the vaccine. However, the presence of proteins that normally are present on each bacterium stimulates your immune system to recognize particular strains and protect against them, in the event that you are ever exposed.

If I receive meningococcal vaccine during pregnancy, can it harm my baby?

Since none of the meningococcal vaccines are live, they are not thought to be potentially harmful to the developing baby, but studies are ongoing to generate evidence for or against safety during pregnancy. Thus far, no association has been found between the MPSV4 vaccine and miscarriage or other negative outcomes in pregnancy. This same vaccine type has been shown to help the baby to develop its own immune response to protect against meningococcus. Because MPSV4 is the best-studied meningococcus vaccine thus far, it is recommended for pregnant women, but this does not mean that MCV4 and the MemB vaccines will be added to the list of vaccines recommended during pregnancy. 

If I receive meningococcus vaccine and become pregnant, what should I do?

Thus far, studies have not revealed that use of the vaccine in a pregnant woman, or just before conception, actually does any harm. Consequently, if you have received any meningococcal vaccine prior to learning that you were pregnant, there is little reason to be concerned. Moreover, if you have not received any meningococcal vaccine and are pregnant, you should receive the MPSV4.

If I am given meningococcus vaccine, can I safely breastfeed my baby?

There is not much information available yet on meningococcus vaccines for breastfeeding mothers, but there is not much of a rationale for any danger.

If I am given meningococcus vaccine, will it be more difficult to get pregnant?

The meningococcus vaccine should not affect your fertility negatively. There have been a very small number of cases of a complication involving the nervous system called Guillain-Barré syndrome developing in people who have received the MCV4 vaccine. However, this is extremely rare and if you are preparing to become pregnant, most likely you will be given the MPSV4 type of vaccine, not the MCV4.

If I am given meningococcus vaccine, what should I know?

You should know that there are no live agents in meningococcus vaccines, so there is no concern about infection of the developing baby.

If I am taking any vaccine, what should I know?

You may find Pregistry's expert report about vaccines during pregnancy here, reports about a variety of vaccines here, and reports about the various medications used for infections here.   Pregistry also offers blog posts about vaccines here. Additional information can also be found in the resources at the end of this report. 

Resources for meningococcal vaccine in pregnancy:

For more information about meningococcal vaccine during and after pregnancy, contact (800-994-9662 [TDD: 888-220-5446]) or check the following links:

Read the whole report
General information

It is very common for women to worry about having a miscarriage or giving birth to a child with a birth defect while they are pregnant. Many decisions that women make about their health during pregnancy are made with these concerns in mind.

For many women these concerns are very real. As many as 1 in 5 pregnancies end in a miscarriage, and 1 in 33 babies are born with a birth defect. These rates are considered the background population risk, which means they do not take into consideration anything about the health of the mom, the medications she is taking, or the family history of the mom or the baby’s dad. A number of different things can increase these risks, including taking certain medications during pregnancy.

It is known that most medications, including over-the-counter medications, taken during pregnancy do get passed on to the baby. Fortunately, most medicines are not harmful to the baby and can be safely taken during pregnancy. But there are some that are known to be harmful to a baby’s normal development and growth, especially when they are taken during certain times of the pregnancy. Because of this, it is important to talk with your doctor or midwife about any medications you are taking, ideally before you even try to get pregnant.

If a doctor other than the one caring for your pregnancy recommends that you start a new medicine while you are pregnant, it is important that you let them know you are pregnant.

If you do need to take a new medication while pregnant, it is important to discuss the possible risks the medicine may pose on your pregnancy with your doctor or midwife. They can help you understand the benefits and the risks of taking the medicine.

Ultimately, the decision to start, stop, or change medications during pregnancy is up to you to make, along with input from your doctor or midwife. If you do take medications during pregnancy, be sure to keep track of all the medications you are taking.