Evidence Indicates mRNA COVID-19 Vaccine Protection for Pregnan

  • It's reported that over 125,000 laboratory-confirmed COVID-19 cases are pregnant women, including thousands of hospitalized cases and 161 deaths by the end of September 2021. Though such an appalling number of SARS-CoV-2 infections happened to pregnant women, most of them are still on the sidelines of getting vaccinated against COVID-19, mainly because of worrying about adverse events to their babies.


    Research on mRNA COVID-19 Vaccine Protection for Newborns


    Due to a low vaccination rate, researchers are dedicated to investigating the presence of transplacental antibody transmission and levels of detectable antibodies in cord blood in pregnant women who are vaccinated against COVID-19, helping people understand the security of COVID-19 mRNA vaccines on pregnant women. This study result is published in the American Journal of Obstetrics & Gynecology MFM.


    In this study, qualified women previously injected COVID-19 vaccines received informed consent and recruitment. Scientists at the New York University collected their umbilical cord blood at delivery to analyze anti-nucleocapsid (anti-N) and anti-spike (anti-S) IgGs by immunoassays. Analyzing antibodies to these two proteins means a lot because antibodies to anti-S IgGs may be present either after natural infection or vaccination, while antibodies to anti-N IgGs are only present following natural infection. In other words, if there is obvious detection of anti-S IgGs but no evidence of anti-N IgGs in umbilical cord blood assays, it possibly will indicate that vaccine-induced immunity is able to transmit from the mother to the fetus in form of transplacental antibody transmission.


    It turns out that 100% of collected samples and newborns in this study were positive for anti-S IgGs, proving that vaccine-induced SARS-CoV-2 IgG antibodies could transfer from pregnant women who accepted COVID-19 mRNA vaccination to fetuses. This is a great advancement based on previous research that antibodies gained through the natural immunity of mothers, who have a history of COVID-19 infection, can be passed to newborns, helping with the immunity of the baby to coronavirus.


    Suggestions on COVID-19 Vaccination to Pregnant Women


    On September 27, 2021, the US Centers for Disease Control and Prevention has issued an urgent coronavirus vaccination recommendation for pregnant women as well as those who have recently given birth. A report from this agency also claimed that women are advised to get vaccinated against coronavirus either before or during pregnancy as the benefits of vaccination outweigh known or potential risks.


    As a matter of fact, since COVID-19 vaccines are not 'live' vaccines, they won't cause infection to people. Existing data shows that there is no increased risk of having adverse pregnancy outcomes for pregnant vaccinated with COVID-19, nor does the vaccine increase the risk of miscarriage, preterm birth, stillbirth, and congenital abnormalities.


    SARS-CoV-2 Vaccines and Its Development


    The principle of SARS-CoV-2 vaccine approaches is to allow the immune system to recognize specific epitopes and produce antibodies against them, which has proven to be very effective in the prevention of COVID-19 infection. SARS-CoV-2 vaccine discovery could be performed through different platforms, including some traditional ones, such as inactivated forms of the virus as well as some newer platforms like mRNA vaccines.


    • Inactivated vaccines


    One approach to developing coronavirus vaccines is to create inactivated vaccines by growing viruses in cell culture and then chemically inactivating them, which means the virus cannot invade cells or reproduce to be infective. SARS-CoV-2 inactivated vaccines along with alum or other adjuvants are often injected intramuscularly, causing immune responses targeting not only the spike protein but also other components of the virus.


    • mRNA vaccines


    As viruses could reacquire traits from the wild-type virus to get reactivated and become infective, mRNA vaccines avoid this issue by only providing the mRNA encoding for antigens. It completely relies on the cell machinery of the host to translate the genetic material and express the target protein, eliciting an immune response. mRNA vaccines were the first approved vaccines for SARS-CoV-2 for production.


    Other vaccine approaches including live attenuated vaccines, recombinant protein vaccines, vector vaccines, and DNA vaccines also contribute to public health policy and advance the development of a SARS-CoV-2 vaccine in different ways.




    Shreds of research evidence show that antibodies both gained from the natural immunity and the mRNA SARS-CoV-2 vaccine-induced immunity could be transferred from pregnant women to fetuses, potentially protecting newborns from COVID-19 infection. Therefore, researchers particularly emphasized that women who are in pregnancy, trying to become pregnant, and are breastfeeding are advised to receive the COVID-19 vaccine.