In an early analysis of coronavirus vaccine safety data, researchers at the Centers for Disease Control and Prevention found no evidence that Pfizer-BioNTech or Moderna vaccines pose serious risks during pregnancy.
The findings are preliminary and cover only the first 11 weeks of the US vaccination program. But the study, which included self-reported data on more than 35,000 people who received one of the vaccines during or shortly before pregnancy, is the largest on the safety of coronavirus vaccines in pregnant women.
During clinical trials of vaccines, pregnant women were excluded. This left patients, doctors and experts unsure whether the vaccines were safely administered during pregnancy.
“There’s a lot of anxiety about whether it’s safe and would work and what to expect in terms of side effects,” said Dr. Stephanie Gaw, a specialist in maternal and fetal medicine at the University of California, San Francisco.
The new data, said Dr. Gaw, shows that “a lot of pregnant women receive the vaccine, there is no significant increase in adverse effects on pregnancy at this time and that the side effect profiles are very similar to people who are not pregnant.”
“I think it’s very reassuring,” she said, “and I think it will really help providers and public health officials recommend vaccination more during pregnancy.”
Covid-19 presents serious risks during pregnancy. Pregnant women who develop symptoms of the disease are more likely to become seriously ill and die more than asymptomatic women.
Because of these risks, the CDC has recommended that coronavirus vaccines be made available to pregnant women, although it also suggests that they consult with their physicians when making a decision about vaccination.
The new study, which was published Wednesday in The New England Journal of Medicine, is largely based on self-reported data from V-safe, the CDC’s coronavirus vaccine safety monitoring system. Program participants use a smartphone app to complete regular surveys about their health and any side effects they may experience after receiving a Covid-19 vaccine.
The researchers analyzed the side effects reported by safe V-participants who received either the Pfizer or Moderna vaccine between December 14, 2020 and February 28, 2021. They focused on 35,691 participants who said they were pregnant when they received or received became pregnant shortly thereafter.
After vaccination, pregnant participants reported the same general pattern of side effects as non-pregnant women, the researchers found: injection site pain, fatigue, headache and muscle aches.
What you need to know about Johnson & Johnson vaccine break in the USA
-
- On April 13, 2021, U.S. health agencies called for an immediate break in the use of the Johnson & Johnson Covid-19 single-dose vaccine after six U.S. beneficiaries developed a rare disorder involving blood clots within one to two weeks. three weeks after vaccination.
- All 50 states, Washington DC and Puerto Rico has temporarily stopped or recommended suppliers discontinue use of the vaccine. The U.S. military, federally administered vaccination sites and a number of private companies, including CVS, Walgreens, Rite Aid, Walmart and Publix, have also stopped injections.
- Less than one in a million Johnson & Johnson vaccinations are now being researched. If there is indeed a risk of blood clots forming in the vaccine – which has not yet been established – this risk is extremely low. The risk of getting Covid-19 in the United States is much higher.
- The break could complicate national vaccination efforts at a time when many states are facing an increase in new cases and are looking to address the vaccine’s hesitation.
- Johnson & Johnson also decided to postpone the launch of its vaccine in Europe amid concerns about rare blood clots, but later decided to resume its campaign after the European Union’s drug regulator said it should added a warning label. South Africa, devastated by a more contagious virus that has appeared there, has suspended the use of the vaccine, and Australia has announced it will not buy any doses.
Women who were pregnant were slightly more likely to report pain at the injection site than women who were not, but less likely to report other side effects. They were also slightly more likely to report nausea or vomiting after the second dose.
Participants who are certainly pregnant in V have also been given the opportunity to register in a special register that tracks the results of pregnancy and infants.
By the end of February, 827 of those registered in the pregnancy register had completed their pregnancies, of which 86% led to a live birth. Rates of miscarriage, prematurity, low birth weight and birth defects were consistent with those reported in pregnant women before the pandemic, the researchers report.
“This study is critically important for pregnant women,” Dr. Michal Elovitz, a specialist in maternal and fetal medicine at the University of Pennsylvania, said in an email. “It is very reassuring that no acute events were reported in pregnant women,” she said during the study.
But the report has more limitations and much more research is needed, experts said. Enrollment in surveillance programs is voluntary and data are self-reported.
In addition, because the study period covered only the first few months of the US vaccination campaign, the vast majority of those enrolled in the pregnancy registry were health care workers. And there are still no data on pregnancy outcomes from people who were vaccinated in the first trimester of pregnancy.
“I think we can be more confident about recommending the vaccine during pregnancy, and especially to pregnant women who are at risk for Covid,” said Dr. Gaw. “It simply came to our notice then you need to wait for more data for complete pregnancy results from vaccines to early pregnancy. ”