“There is really no theoretical reason to believe that this will harm the mother or the unborn child and we are very confident that it will provide considerable benefits for both the mother and the baby,” said Beigi, who is president of UPMC Magee-Womens Hospital in Pittsburgh.
Only a few people, such as those with severe allergies, a history of anaphylactic shock or who are suffering from advanced cancer would probably be advised to avoid the vaccine. Any pregnant woman with concerns should speak to her OB-GYN, experts say.
“US regulatory bodies and medical experts have clearly stated that all eligible pregnant women should have the option to receive the vaccine,” said Dr. Christopher Zahn, vice president for practical activities at ACOG.
An international controversy
It is a strong and clear message that obstetric gynecologists and medical associations hope to reach pregnant women and their families, who may be confused about the conflicting recommendations made this week by the World Health Organization.
But any “potential vaccine risks” mentioned by the WHO are purely speculative, doctors tell CNN, in comparison to Covid-19’s known risks to pregnant women and their babies.
“The lack of data is not equivalent to the risk of harm – especially when science and basic biology do not suggest a plausible reason why harm could occur,” said Dr. Kjersti Aagaard, a specialist in maternal and fetal medicine at Texas Children’s Full professor at the Hospital and Meyer in obstetrics and gynecology at Baylor College of Medicine.
The doctors who spoke to CNN said that there are decades of safety data showing that inactivated vaccines do not harm a pregnant woman or her baby – and they believe the data should also apply to Moderna and Pfizer vaccines, which are not made from a live virus.
Instead, they are mRNA vaccines, which teach cells in the body how to make a piece of a protein that triggers an immune response. Once the instructions are given, “the cell breaks down and gets rid of the mRNA”, according to the CDC.
Therefore, WHO’s concerns are “more focused on hypothetical risks at the expense of recognizing the clear benefits of immunization,” said Beigi. “This can be very confusing for a woman, which is unfortunate, very unfortunate.”
The risks of Covid-19 during pregnancy are significant
At the beginning of the pandemic, it appeared that Covid-19 did not negatively affect women or their babies during pregnancy. As the data arrived, however, that belief changed dramatically.
“Pregnant women are up to five times more likely to be hospitalized, three to four times more likely to need care in an ICU and two to three times more likely to need life-saving measures, such as getting a breathing tube or being placed about advanced life support, “said Aagaard, who has a doctorate in immunology.
“And while the data is not yet complete, there is at least a small risk of maternal and stillbirth and premature birth with Covid-19 disease during pregnancy,” continued Aagaard. “Black and Latino women are at an especially increased risk of serious illness and death because of Covid-19. Those are the facts.”
Why would pregnancy put women at greater risk? One reason is the decrease in the woman’s lung capacity as the baby grows.
“You can develop respiratory impairment, to the point where you cannot recover,” said Aagaard. “For every pandemic we’ve had in the past 100 years, there has been an increased risk for pregnant women when these pandemics are associated with serious respiratory illnesses.”
In addition, Aagaard said, a pregnant woman’s heart beats 1.5 times faster than usual to provide adequate blood for the baby and the placenta.
“Therefore, this excessive action of the heart, which we call increased cardiac output, also puts pregnant women at risk for heart failure problems, which can be a manifestation and potential cause of death from Covid-19 disease,” she said.
Pregnant women may also have an overly enthusiastic immune system, which can lead to the so-called cytokine storm, which signals more serious illnesses and negative results, Aagaard said.
And finally, there is an increased likelihood of blood clotting during pregnancy, which Covid-19 tends to make worse.
“Humans, like all placental mammals, are at risk of bleeding to death after the placenta separates from the wall of the uterus,” said Aagaard. “So 4.5 million years of evolution are on our shores, helping us to clot a little more effectively when we are pregnant.”
Benefits for the baby?
Although this study has not examined whether antibodies created by vaccination would also cross the placenta, the concept has been used in maternal medicine for some time.
Pregnant women receive the inactivated flu vaccine and a so-called TDAP, which protects the mother and baby from tetanus, diphtheria and whooping cough, also known as whooping cough.
“Wouldn’t it be incredible if we could make such a beautiful transition from our developing fetus to go out into the protected world of Covid-19?” Said Aagaard. “If we could arm that baby with its own memory cells, it would be a double, which is what we always expect.”
A different emphasis
While US and WHO officials are clear about the lack of safety data in their guidelines, a WHO spokesman said the agency is putting more emphasis on “guidance that can inform immunization program decisions” during “current limitations on global vaccine supply”. The position of the CDC and the USA focuses on “individual decision making”.
“As there is a lack of data on the presence or absence of risks associated with the vaccine in pregnancy, at this time WHO could not provide a comprehensive recommendation for vaccination of pregnant women, except among those who fall into the highest priority groups for which vaccination is needed. is now recommended in countries, “the spokesman told CNN via email.
“I think the fact that they are saying that we do not recommend this will have an effect in many countries,” said ACIG’s Beigi, “because the medical leaders in those countries will be much more reluctant.”
Zahn, also from ACOG, agreed.
“We are concerned that conflicting recommendations may undermine the confidence of all patients who consider this vaccine to be potentially saving,” said Zahn. “We strongly encourage vaccination programs to follow the guidance of US health officials and medical experts so that pregnant women do not face barriers to vaccination.”
Trials of various sizes are underway, and doctors point to the large number of pregnant women who have received the Covid-19 vaccines since they were launched – with no known side effects. That makes sense, said Texas Children’s Aagaard.
“Not only have I been in obstetrics for a few decades, but my PhD is in immunology,” said Aagaard. “And I really can’t imagine what biology or science would be to explain why a pregnant woman or her fetus would be at greater risk than a non-pregnant woman.”
Although he appreciates the “nuance” that WHO is using to prioritize, Aagaard said he remains confident in “our ability to walk and chew gum at the same time”.
“We are fully capable of vaccinating all those in need, including those most at risk of harm. This includes pregnant women, who represent about 3% to 5% of the world’s female population at any given time,” said Aagaard.