Covid-19 and Vaccines Recommended for Pregnant Mothers

When it comes to administering medication or vaccines to pregnant mothers, there are always questions about whether it is safe. Will the medication or vaccine affect the mother’s health or the pregnancy? Is there a chance it could cause birth defects or harm the baby in the womb?

Recommendations for Vaccination for Pregnant Mothers

According to the latest information from the U.S. Centers for Disease Control and Prevention and vaccination guidelines in Thailand, there are 3 important vaccines recommended for pregnant mothers:

1. Covid-19 vaccine, which should be given to pregnant women over 12 weeks of gestation
2. Influenza (Flu) vaccine, starting from 14 weeks of gestation
3. Tdap vaccine (Tetanus, Diphtheria, Pertussis), given between 27-36 weeks of gestation

Since there are currently no vaccines to prevent Covid-19, influenza, and pertussis for newborns, vaccinating pregnant mothers plays a role in passing immunity to the baby in the womb. This provides the baby with immunity from birth, a period when they cannot receive vaccines against these infections. If infected, the baby has a higher chance of severe illness or death, especially from Covid-19.

3 Vaccines and Important Information

Covid-19 Vaccine for Pregnant Mothers

Covid-19, or Coronavirus Disease 2019, is a disease that causes respiratory tract infections, which can lead to severe pneumonia and death. Data from the Royal Thai College of Obstetricians and Gynecologists shows that pregnant women have a 2-3 times higher chance of severe symptoms requiring ICU admission and a 2.6-2.9 times higher chance of needing mechanical ventilation, especially if risk factors are present such as age over 40, obesity, or chronic diseases like diabetes. The mortality rate is 1.5-8 per 1,000 cases.

Previous studies show that if a mother is infected during delivery, Covid-19 virus is usually not detected in breast milk but can be found on the skin of the breast. Infected mothers have a 1.5 times higher chance of preterm birth, a 2.8 times higher chance of stillbirth (baby born without signs of life), and a 3-5% chance of the baby being infected.

Because of the high severity risk in pregnant women, Covid-19 vaccination is very beneficial in building immunity to prevent infection, reduce disease severity, and lower the risk of death. It is recommended for all pregnant women after 12 weeks of gestation, except those with a history of allergy to vaccine components.

Mothers can receive Sinovac, AstraZeneca, or mRNA vaccines. Two doses are required, with different intervals between doses: Sinovac and mRNA vaccines are given 4 weeks apart, while AstraZeneca doses are 12 weeks apart. Covid-19 vaccination should be spaced 2-4 weeks apart from other vaccines given during pregnancy.

Influenza Vaccine for Pregnant Mothers

Influenza is a disease that can cause severe complications and increase mortality rates in pregnant women. It increases the risk of preterm birth by 2-4 times, the risk of low birth weight by 2 times, and the risk of fetal death by 2-4 times.

Many medical studies have found that influenza vaccination in pregnant women helps reduce the severity of illness in the mother and lowers the chance of the baby contracting influenza. Vaccination is important because the mother’s weakened immune system makes her more susceptible to infection and severe symptoms. Vaccination builds immunity that is passed through the placenta and umbilical cord to the baby, protecting the newborn who cannot yet receive the vaccine. It can be given from 14 weeks of gestation. Because the virus frequently mutates, vaccines covering the most prevalent strains in the country each year should be selected.

Pertussis Vaccine for Pregnant Mothers

Pertussis, or whooping cough, is a respiratory infection caused by bacteria. Infection in newborns is much more severe than in adults. In severe cases, coughing fits occur without breaks, followed by a strong inhalation causing a characteristic “whooping” sound. Some cases may develop pneumonia or life-threatening complications. The key prevention is the Tdap vaccine (tetanus, diphtheria, pertussis) given to pregnant women between 27-36 weeks of gestation to transfer immunity through the placenta and umbilical cord to protect the baby during the first 3 months of life.

Due to lowered immunity in pregnant women, co-infections increase the risk of death and pregnancy complications. Vaccination covering all three diseases is important, with each dose spaced 2-4 weeks apart. The timing of vaccination and type of Covid-19 vaccine should also be considered, as intervals vary, for example:

If using inactivated vaccines (Sinovac) or mRNA vaccines (Pfizer, Moderna), two doses are required with a 4-week interval, which may be scheduled as follows:

If using viral vector vaccines (AstraZeneca), two doses are required 12 weeks apart, which may be scheduled as follows:

In the Covid-19 pandemic situation, pregnant women are at very high risk both in terms of infection and disease severity. Therefore, vaccination is an urgent preventive measure that should be administered as soon as the pregnancy reaches the appropriate gestational age. Other necessary vaccines for pregnant women, which have different timing schedules, should also be given. Pregnant women are advised to consult their doctors early to arrange a vaccination schedule that covers all necessary vaccines and provides the best protection.