# Covid Vaccine and Pregnancy: What Years of Data Actually Show
Recent claims from prominent Republicans questioning the safety of covid vaccines during pregnancy contradict what researchers have documented over the past three years. The scientific evidence accumulated since 2021 demonstrates that vaccination before and during pregnancy protects both mother and developing fetus.
The Centers for Disease Control and Prevention, along with the American College of Obstetricians and Gynecologists, recommend covid vaccination for pregnant people. This guidance rests on data collected from hundreds of thousands of pregnancies tracked through multiple surveillance systems.
The V-safe pregnancy registry, which monitors nearly 3,000 pregnant people who received mRNA vaccines, found no increased risk of miscarriage, stillbirth, or birth defects. Researchers at Brigham and Women's Hospital published findings in 2021 showing vaccination rates of miscarriage matched rates in the general population. A subsequent study tracking over 200,000 pregnancies in the United States found no safety signal for adverse pregnancy outcomes among vaccinated individuals.
Unvaccinated pregnant people face documented risks. Covid infection during pregnancy increases the risk of severe illness requiring hospitalization. Infected pregnant people show higher rates of preeclampsia, premature birth, and delivering babies with lower birth weight. Studies from the CDC found that pregnant people hospitalized with covid had worse outcomes than vaccinated pregnant people who still contracted the virus.
The vaccine works by teaching the immune system to recognize the spike protein. The mRNA does not enter cell nuclei or alter DNA. After delivering instructions, the mRNA breaks down within days. The lipid nanoparticles carrying the vaccine disperse throughout the body but do not accumulate in reproductive organs specifically.
Data on maternal antibodies offers another reassuring finding. Vaccinated pregnant people pass protective antibodies to their fetuses, conferring temporary immunity to newborns during their most vulnerable months. Infants born to vaccinated mothers showed lower rates of covid infection in their first months of life.
Healthcare providers emphasize that the timing matters. The CDC recommends vaccination at any point during pregnancy, though some practitioners prefer the second and third trimesters to avoid confusing pregnancy symptoms with vaccine side effects. Common side effects like fatigue, headache, or arm soreness mirror those seen in non-pregnant people.
The stakes of remaining unvaccinated during pregnancy remain high. Pregnant people infected with covid face increased risk of severe pneumonia, blood clots, and maternal death. The virus also carries small risks of adverse fetal outcomes.
Researchers continue monitoring pregnancies through ongoing registries and studies. No new safety concerns have emerged in recent surveillance data. Public health authorities acknowledge that vaccine hesitancy exists among some pregnant populations and emphasize transparent communication about both the risks of infection and the established safety profile of vaccines.
For pregnant people deciding on vaccination, the evidence points in one direction. The risks from covid infection during pregnancy exceed the risks from the vaccine itself. Discussion with an obstetrician or midwife can address individual circumstances and concerns.