A study has found that pregnant women who receive their first messenger RNA–based COVID-19 vaccine during their pregnancy, produce antibodies for COVID-19 as early as five days following inoculation. The study also found that within 16 days following the first vaccination, the immunity can pass through transplacental transfer to the neonate as early as 16 days after the first vaccination dose. The study included 122 pregnant women with cord blood available from Jan 2021- March 2021. The pregnant women included reported when they received of the first or second, or both doses of a messenger RNA (mRNA)–based COVID-19 vaccine, and only included those who gave birth to a singleton neonate of a gestational age between 35 0/7 and 41 2/7 weeks. Further studies are needed to completely understand the nature and impact of the transplacental transfer of the IgG antibodies
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