Reassuring research in COVID-19 vaccination during pregnancy

As is usual with large scale vaccination programmes, a rumour mill has started up with all kinds of misinformation and sometimes outright disinformation circulating. It is not unusual to see all kinds of bizarre comments on social media covering topics like:

• The COVID-19 vaccine is the tool of some kind of global eugenics programme
• The vaccine contains pork and other animal products
• It causes infertility
• It kills more people than COVID-19 itself
• It doesn’t work, is unnecessary, and can be replaced with anything from oranges to expensive colloidal silver preparations
• It is dangerous in the long term, and we won’t know for years
• It is dangerous in pregnancy.

This is by no means an exhaustive list. Some of these rumours are passively floated by media only interested  in audience ratings. Others are maliciously assembled by other parties who are either cranks, charlatans or quack medicine sellers to fill what are known as information gaps.

Take the last one, it is dangerous in pregnancy? This arises from the information gap in the Phase III trial data of the vaccines. For example, in the case of the Moderna and Pfizer vaccines, not enough information was available from the trials to assess risk in pregnant women, according to these manufacturers.

Current guidelines

As a result, there has been some ambiguity in guidelines for use of the vaccine in pregnant women:

• Centers for Disease Control (CDC): The CDC included pregnancy along with other underlying conditions that qualify people to be offered vaccines in the third priority tier (Phase 1c)¹
• American College of Obstetrics and Gynecology (ACOG): AOCG recommends that COVID-19 vaccines should not be withheld from pregnant individuals.²
• World Health Organisation (WHO): WHO, in contrast, recommends the vaccines only for pregnant women who are at high risk of exposure to SARS-CoV-2 (e.g., health workers) or who have comorbidities, which add to their risk of severe disease.³

The vaccine manufacturers had anticipated that the issue of pregnancy would create ambiguities, which would need to be addressed at some point. With this in mind, Pfizer had already announced that it would begin a follow-up trial of its vaccine in healthy pregnant women⁴.

Voluntary reporting

In the meantime, reassuring data on use of the Pfizer and Moderna vaccines in pregnancy has emerged in the US via the CDC’s V-Safe voluntary reporting system. More than 30,000 women who received the vaccines have reported pregnancies through V-Safe and their rates of complications are not significantly different from those of unvaccinated pregnant women.

Unveiling data

Unveiling the new data during a March 1 meeting of the Advisory Committee on Immunization Practices (ACIP)⁵, Dr Tim Shimabukuro, deputy director of the CDC Immunization Safety Office said, “Overall, the data are reassuring with respect to vaccine safety in pregnant women. There is evidence that pregnant women who get COVID-19 are at increased risk of severe illness and complications from severe illness. And there is also evidence that pregnant persons who get COVID-19 may be at increased risk for adverse pregnancy outcomes.”

Latest data

At the time of the study, V-Safe recorded 55,220,364 reports from people who received at least one dose of the Pfizer or Moderna vaccine up to 16 February 2021. These included 30,494 pregnancies, of which 16,039 were in women who received the Pfizer vaccine and 14,455 in women who received the Moderna vaccine. Analysing the data, the researchers found that both local and systemic reactions were similar between pregnant and nonpregnant women.

Pregnancy outcomes following vaccination against COVID-19

Protecting infants

While the new safety data in respect of pregnancy is reassuring, US government medical experts also continue to make the point that vaccination during pregnancy may benefit newborns. The unborn children of pregnant women who receive the vaccine could be protected from the SARS-CoV-2 virus for the first months of their lives.  Dr Anthony Fauci, Government Spokesman, at a recent White House briefing said, “We’ve seen this with many other vaccines. That’s a very good way you can get protection for the mother during pregnancy and also a transfer of protection for the infant, which will last a few months following the birth.”

Impact on fertility

That will have to wait for long-term epidemiological studies as the CDC did not collect data on fertility in this short period. However, there is no evidence to date that the vaccines will have a future adverse effect on fertility. Dr Shimabukuro, speaking for CDC said, “We’ve done a lot of work with other vaccines. And just from a biological basis, we don’t have any evidence that vaccination, just in general, causes fertility problems.”