Ensuring a Healthy Pregnancy: The Importance of Immunizations

Immunization is an important aspect of pregnancy, and it gives tremendous benefits to the mother and the unborn child. It is an active immunity for the mother and passive immunity for the fetus. Most women fear vaccination during pregnancy, thinking it might cause harm to the fetus, but this is not the case. There is no evidence of any harmful effect on the foetus' post-maternal vaccination. Live bacterial and live attenuated vaccines pose a theoretical risk and are contraindicated in pregnancy. The benefits of vaccinating pregnant women usually outweigh the potential risks when the likelihood of disease exposure is high; that is, not vaccinating the mother will do more harm than vaccinating her. Given below is a composite list of vaccines and information related to them.

Why Immunizations Matter During Pregnancy?

The antibodies produced by mothers in response to vaccines not only safeguard their own health but also traverse the placenta, providing early protection for their infants against serious diseases. Vaccinating during pregnancy serves a dual purpose by shielding both the mother and the newborn from the risk of serious diseases, preventing the transmission of illnesses from the mother to the baby:

• Prevention of Maternal Infections- Immunizations help prevent infections that can be particularly harmful to pregnant women. For example, vaccines against influenza (flu) and tetanus can protect pregnant women from illnesses that may lead to severe complications or even death.
• Protection of the Unborn Child- Certain infections can have harmful effects on the developing fetus. Immunizing pregnant women helps create a protective shield, as some of the antibodies produced in response to vaccines can pass through the placenta, providing passive immunity to the newborn during the early months of life.
• Reduction of Maternal Mortality- Infections such as influenza and tetanus can be life-threatening for pregnant women. By preventing these infections through timely immunizations, the risk of maternal mortality is significantly reduced, contributing to the overall well-being of expectant mothers.

• Prevention from Transmission-? Some infections can be transmitted from mother to child during childbirth. Immunizations, such as those for hepatitis B, can help prevent vertical transmission, protecting the newborn from potential lifelong consequences of the infection.
• Promotion of a Healthy Pregnancy- Immunizations contribute to a healthier pregnancy and reduce the risk of complications such as preterm birth or low birth weight. Maintaining good health during pregnancy is essential for the well-being of both the mother and the child.
• Support for Maternal Immune System- Pregnancy can alter a woman's immune system, making her more susceptible to certain infections. Immunizations help support the maternal immune system by providing targeted protection against specific pathogens, ensuring that the mother is less likely to fall ill during pregnancy.
• Prevention of Congenital Infections- Some infections, such as rubella (German measles), can cause congenital disabilities if contracted during pregnancy. Immunizing women before they become pregnant or during the early stages of pregnancy helps prevent congenital infections and their associated complications.

Important Immunizations Recommended During Pregnancy

COVID 19

COVID-19 vaccination is considered safe for pregnant women and also for women who are trying to get pregnant. It is even regarded as safe for breastfeeding women.? COVID-19 is a deadly disease, and all pregnant women need protection against it. Although we have limited data regarding this vaccine as it is a relatively new vaccine, its safety profile is increasing with increasing evidence.

Hepatitis A

Hepatitis A vaccination during pregnancy is not routinely given, nor is it a part of the antenatal immunization schedule of pregnant women. But, it can be given if the benefits of vaccination are more than the risks during a hepatitis A outbreak, as hepatitis A infection can be fatal during pregnancy.

Hepatitis B

Pregnancy is not a contraindication to vaccination. Limited data suggest that developing fetuses are not at risk for adverse events when the hepatitis B vaccine is administered to pregnant women. Available vaccines contain noninfectious HBsAg and should cause no risk of infection to the fetus.? If no prior vaccination with hepatitis B? is done, pregnant ladies should receive the vaccination.

Human Papillomavirus (HPV)

HPV vaccines are not recommended to be used in pregnant women; if accidentally given to pregnant women, the remainder of the dose should be withheld till the pregnancy is over.

Influenza (Inactivated or Recombinant)

Women who are planning a pregnancy or are pregnant during an influenza outbreak or influenza season should receive inactivated or recombinant influenza vaccine, as pregnant women face severe danger and risk of severe complications and fatality from contracting influenza when pregnant.

Measles, Mumps, Rubella [MM]

MMR vaccines are contraindicated during pregnancy because it is a live viral vaccine and theoretically can cause a risk of congenital rubella syndrome in the fetus. Women who are vaccinated should avoid becoming pregnant at least 4 weeks post-vaccination. Rubella-susceptible women who are not pregnant should be vaccinated, and those who are not vaccinated should receive vaccination as soon as the pregnancy is over.

Meningococcal (MenACWY or MPSV4)/ Meningococcal (MenB)

It should not be used as a routine vaccine during pregnancy. It should not be administered to pregnant and lactating mothers unless the woman is at increased risk or there is a disease outbreak when the benefits of vaccination are considered to outweigh the potential risks.

Polio [IPV]

IPV is an inactivated polio vaccine. The inactivated polio vaccine has not been shown to have any adverse effects on pregnant women or their pregnancies. Still, it is not recommended to administer this vaccine to pregnant women based on theoretical risk. However, in special circumstances where there is an increased risk of contracting the disease by pregnant women, and they need immediate protection, IPV? can be administered as per the adult schedule of the vaccine.

Tetanus, Diphtheria, And Pertussis (TDAP); AND Tetanus And Diphtheria (TD)

TDAP is a part of the routine immunization schedule for pregnant women. Every woman should receive one dose of TDAP during each pregnancy, irrespective of prior vaccination status. The optimal timing for TDAP administration is between 27 and 36 weeks of gestation to maximise the maternal antibody response and passive antibody transfer to the infant. Although TDAP may be given at any time during pregnancy, it has been postulated that vaccination during this time of gestation will lead to maximum antibody transfer to the infant. For women not previously vaccinated with TDAP, if TDAP is not administered during pregnancy, Tdap should be administered immediately postpartum.?

Varicella

Pregnant women should not be routinely vaccinated for rubella; women who get vaccinated should avoid conception for 1 month. If a pregnant woman accidentally receives MMR OR varicella vaccine or conceives within 4 weeks of vaccination, they should be informed about the theoretical basis of concern for the fetus; however, MMR or varicella vaccination during pregnancy should not be considered a reason to terminate pregnancy.

Anthrax

In a pre-event setting, in which the risk for exposure to anthrax aerosolized is low,?vaccination of pregnant women is not recommended. In settings where there is a high risk of exposure to anthrax, pregnancy is not considered a contraindication to vaccination. Pregnant women at risk for inhalation of anthrax should receive AVA and 60 days of antimicrobial therapy as described.

Japanese Encephalitis (JE)

Immunization during pregnancy may be considered if travel to an area with endemic infection is unavoidable and the risk of disease outweighs the risk of adverse events in pregnancy.

Rabies

Pregnancy is not considered a contraindication to post-exposure prophylaxis of rabies. Rabies exposure or diagnosis of rabies in the mother should not be regarded as reasons for pregnancy termination.

Typhoid

Live vaccines like Ty21a are contraindicated in pregnancy. The polysaccharide vaccine can be given to pregnant women if needed.

Yellow Fever

Pregnancy is a ‘precaution’ for YF vaccine administration, compared with most other live vaccines contraindicated in pregnancy. It is the only live viral vaccine that can be administered during pregnancy if needed or if travel to endemic regions is unavoidable.?

Conclusion?

Vaccination is vital during pregnancy because not only is it protective for pregnant mothers, but it also provides protection to newborn infants and protection to them through the passage of passive antibodies. Tetanus toxoid, Tdap, and influenza vaccines are mainly given; other vaccines like hep B and yellow fever can be given after evaluating the risk-benefit ratio. So, vaccination is a safe choice for pregnant women, and it should be taken seriously to avoid any untoward effect on the mother and the child.