Covid-19 vaccines leave pregnant women for a while

“What is the risk to my child if I get the vaccine?” That empty space, that area with no data to know what the effects would be, is really worrying, “said Jennifer Lewey, a 40-year-old cardiologist at the University of Pennsylvania Hospital on March 21.

The dilemma facing expectant mothers such as Dr. Lewey, who has decided to give up vaccination for the time being and rely on masking and other precautions, highlights a gap in the examination of Covid-19 vaccines during their rapid development: they do not have have been tested in pregnant women.

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The companies behind two US-licensed Covid-19 vaccines did not enroll pregnant women in late-stage studies to assess whether work fires work safely.

Missing data, the U.S. Centers for Disease Control and Prevention, the American College of Obstetricians and Gynecologists, and the Society of Maternal and Fetal Medicine say pregnant women should make their own decisions, encouraging conversations with doctors.

Citing insufficient data, the World Health Organization, meanwhile, has generally recommended against shooting during pregnancy, with the exception of high-risk people such as health workers or those with certain health problems. But on Friday, the WHO also said on its website that “we have no specific reason to believe that there will be specific risks that would outweigh the benefits of vaccination for pregnant women.”

Michal Elovitz, an obstetrician-gynecologist and director of the University of Pennsylvania’s Maternal and Child Health Research Center, said he leaves the choice to his patients after discussing the potential benefits and risks.

Expectant mothers are more likely to have a severe case of Covid-19 than women who are not pregnant and are more likely to need a premature birth if they contract the disease, Dr. Elovitz said. The vaccine may help reduce the risks. Some vaccines for other infections have also been shown to be safe during pregnancy and provide protection for both mother and baby, she said.

Most experts say they do not anticipate any problems, based on the functioning of mRNA vaccines. However, scientists still do not know if the mRNA vaccine can cross the placenta and, if possible, scientists do not know if it would harm the fetus, say experts in maternal and fetal health. This type of vaccine was never used during pregnancy, they say. Pfizer and Moderna vaccines use a gene-based technology called messenger RNA, which was never eliminated for use until the pandemic.

Uncertainty makes the choice of vaccination very challenging, say pregnant women.

“It was a difficult decision,” said 37-year-old Brenda Manning, who is currently eligible to receive the vaccine in Dallas, where she lives.

Ms. Manning has limited exposure to Covid-19 because she is a stay-at-home mom whose husband works from home. However, pregnancy and high blood pressure put her at a higher risk of having a severe case of Covid-19 if she receives it.

After weighing her options, Ms. Manning decided to sign up for the vaccine, although she was not given a date for the first dose. He thinks he can make one last call if he receives an appointment before the Feb. 14 deadline.

“If I am called to do this first [the baby] come on, I’ll make a decision during the game, “she said. “And if I don’t get a chance to get the vaccine before that, that’s my answer.”

About 39% of pregnant women surveyed by the University of California, San Diego and the MotherToBaby pregnancy counseling group said they would not receive a Covid-19 vaccine if it was available to them, while 25% said they would not receive it. a vaccine during breastfeeding.

Thirteen percent said they would not receive the vaccine regardless, according to the survey, which began in October and continues.

Christina Chambers, a professor of pediatrics at the University of California, San Diego, who is helping lead the survey as part of studies on how Covid-19 and vaccines affect pregnancy and breastfeeding, said women are hesitant about the lack of information.

Dr. Chambers said more pregnant women are expected to feel comfortable with vaccinations as the launch continues.

The delay in establishing the safety of Covid-19 vaccines in pregnant women and fetuses stems in part from delays in animal testing, said Ruth Faden, founder of the Johns Hopkins Berman Institute for Bioethics, which helps lead the PREVENT project, which advocates for the inclusion of pregnant women. in the development of vaccines during pandemics.

The US Food and Drug Administration recommends animal studies before researchers test vaccines on pregnant women.

Moderna says the vaccine had no adverse effects on reproduction or development during testing in rats. The company intends to set up a register to monitor how mothers who received the vaccine during pregnancy and their babies.

Pfizer says it has completed an animal study and submitted FDA data. The European Medicines Agency has stated that animal studies have shown that the Pfizer vaccine has no harmful effects on reproduction or development. Pfizer says it will begin a study on the maternal vaccine in the first half of 2021.

Pfizer and Moderna say they are watching what happens to those who became pregnant after vaccination, as well as to any pregnant women who went through pre-vaccination screening during their studies.

The UK did not initially include women who were pregnant or will soon become pregnant at the launch of the vaccine in December. Public Health England updated its guide in January, however, saying that vaccination could be particularly important for those who are extremely exposed to the virus or have certain health conditions that underlie a high risk. In these cases, women can choose to receive the vaccine after having a discussion with their doctor or nurse, the agency said.

In January, the Israeli Ministry of Health updated its guide to recommend the vaccine to pregnant women, especially those with pre-existing medical conditions and those with high public exposure.

Write to Sarah Toy at [email protected] and Laura Cooper at [email protected]