Pregnancy Considerations Amidst Differing COVID-19 Vaccines

Feb 25, 2021


For many people, worldwide distribution of the COVID-19 vaccines has inspired hope for herd immunity and relief from the rising death toll and pandemic-associated strain on hospitals and the economy.  As reported by the companies, the currently available Emergency Use Authorized (EUA) mRNA vaccines by Moderna and Pfizer/BioNTech together included general population study data of  approximately 40,000 people. Though the research data was limited, their reporting shows promising efficacy and safety. 

Compared to their non-pregnant peers, pregnant women continue to be a population with increased risk of higher complications from the virus caused by COVID-19. This group, however, was expectedly excluded from the initial clinical trial studies. Complications for pregnant women can include higher risk for severe disease requiring ICU admission, premature birth, and thus complications for the premature infant including respiratory distress and infection. 

Conflicting Expert Guidance Has Led to Hesitancy and Confusion

Expert medical associations have given conflicting guidance on the use of the COVID-19 vaccine for pregnant women. Due to lack of safety data, the World Health Organization (WHO) initially advised women not take one of the mRNA-containing vaccines unless listed among the groups at higher risk for contracting/suffering from COVID-19 (e.g, healthcare/frontline workers, certain medical conditions, etc.). Approximately one week later, with limited data based on animal studies, the WHO changed their stance and stated there are no specific concerns for safety to mother/baby at this time and vaccination may be provided to pregnant women after discussion with their healthcare provider. 

Since the FDA granted EUA for the Moderna and Pfizer/BioNTech COVID-19 vaccines in December 2020, the American College of Obstetrics and Gynecology (ACOG) and Society for Maternal Fetal Medicine (SMFM) have been unwavering in their statement.  Both ACOG and SMFM have announced women should not be denied the administration of the Moderna and Pfizer/BioNTech COVID-19 vaccines and encourage discussions with their healthcare provider. The CDC echoes ACOG and SMFM with respect to allowing pregnant women to receive the COVID-19 vaccination, especially in the place of high risk for exposure such as front line healthcare workers. The WHO is now also in line with the CDC and ACOG. 

Researchers recently announced a formal clinical trial study of the Pfizer mRNA COVID-19 vaccine for pregnant women. Phase 3 clinical trials of the Janssen Biotech/Johnson & Johnson single-dose vaccine includes data which projects the vaccine offers protection against moderate to severe disease caused by COVID-19. It is unclear whether there will be endorsement of this vaccine for pregnant women by the expert medical groups. 

How the DNA-Containing Johnson & Johnson Vaccine Differs from Moderna & Pfizer

In contrast to the currently endorsed mRNA vaccines, the Johnson & Johnson COVID-19 vaccine utilizes DNA of the spike protein attached to a replication-defective adenovirus vector (note: adenovirus is a common cold virus), to enter the nucleus of the recipient’s cells and activate antibody production. There is currently no released data confirming the DNA contained in this type of vaccine cannot infiltrate the genome of a fetus if given to a pregnant woman (though a mouse study using DNA from a different virus and transported as part of an adenovirus did not appear in the DNA of mice when the adenovirus was injected into the male organs of the mice). 

As with all vaccines, pregnant women must make individualized decisions, with the help of their healthcare providers, that consider all known risk factors and safety data. The Pew Research Center has released polling data that show American women are 6-18% more likely than men to have vaccine hesitancy. For families to make the best decisions for themselves, we need more information, including studies performed with proper consent.

Dr. David Berger, the founder and medical director of Wholistic Pediatrics & Family Care, was selected to speak to the FDA’s EUA panel regarding the Janssen Biotech/Johnson & Johnson COVID-19 vaccine. At this February 21, 2021 meeting, he will express concerns regarding DNA-containing vaccine safety for pregnant women and unborn fetuses. He plans to call for more transparent data and more active steps to bridge the gap between the safety of pregnant women and the lack of clinical studies at this time.