Two new studies confirm that giving mRNA vaccines against COVID-19 during pregnancy is safe for both mother and baby. It does not increase the risk of miscarriage, premature birth, stillbirths or complications during pregnancy and childbirth.
These results published in the Journal of the American Medical Association (JAMA) should therefore reassure pregnant women and encourage them to get vaccinated, knowing that they are more likely to develop a severe form of COVID-19 during their pregnancy and, in such a case, to give birth prematurely.
One of these two articles describes the study of an Ontario cohort of some 100,000 pregnancies.
In their analysis, Deshayne Fell of the University of Ottawa and colleagues found no increase in late-pregnancy complications among the 22,660 women who received at least one dose of vaccine during their second or third trimester of pregnancy. pregnancy (i.e. 23% of the cohort), compared to what was observed in women who had not been vaccinated during their gestation.
Vaccinated mothers were not more likely to develop an infection of the membranes that protect the baby, they did not need an emergency caesarean section more often and they did not experience excessive bleeding during childbirth, “as much indicators that testify to the healthy course of pregnancy and birth,” underlines Ms.me Fell, who led this study.
Babies of women vaccinated during pregnancy were no more likely than those of unvaccinated women to require transfer to a neonatal intensive care unit or to have a low Apgar score, a test that is performed five minutes after birth. birth and which aims to assess various vital signs of the baby.
The second article published in the same edition of JAMA details the analysis of approximately 160,000 pregnancies that occurred in Sweden and Norway. This study found no increased risk of preterm birth, stillbirth, low birth weight baby, low Apgar score infant, or infant requiring medical attention. neonatal care among the 28,500 women who were vaccinated during pregnancy (i.e. 18% of the cohort).
Reassuring results
These results bring good news for pregnant women, especially since they are consistent with those of studies carried out in the United States and Israel, conclude the authors of an editorial published in the JAMA.
“The very large number of people who were vaccinated during their pregnancy allowed us to see whether rare complications were more frequent in women who were vaccinated during their pregnancy. However, it is very reassuring to see that in three different countries (Canada, Sweden and Norway), in three different populations subject to different policies, we come to the same conclusions,” adds Ms.me fell.
The risks of not getting vaccinated
In the Department of Obstetrics at the MUHC, which he directs, Dr.r Richard Brown claims to have noticed neither particular problems nor sequelae in women vaccinated before or during their pregnancy.
“Even if they were not very numerous, all pregnant women [suivies au CUSM] who got really sick were those who weren’t vaccinated. In addition, we had to carry out premature deliveries a little more often in unvaccinated women who were sick due to COVID-19, ”he says.
Several studies conducted around the world have shown that pregnant women who contract COVID-19 are at greater risk – 2.4 times more than other women – of serious complications requiring hospitalization, intensive care or respiratory assistance. They are also more likely to jeopardize their pregnancy, give birth prematurely and give birth to a stillborn baby, recalls Ms.me fell.
For the DD Isabelle Boucoiran, from the CHU Sainte-Justine, who is leading the Quebec component of a Canadian study on COVID-19 in pregnant women, miscarriage is not what we fear most: it is rather ” the risk that they end up with severe respiratory distress and that the latter becomes complicated and leads to premature delivery”.
According to the DD Boucoiran, among pregnant women who contract COVID-19, those over 35 and those who are obese are twice as likely to end up in intensive care, those with hypertension are three times more likely, and those who are infected during the third trimester of their pregnancy four times more likely. “It is very important to be vaccinated before the third trimester, because this is when the risk of developing a severe form of COVID-19 is highest,” she warns.
An American study has shown that vaccination during pregnancy reduces the risk that the pregnant woman, but also her child, will develop a severe form of COVID-19. “We see that when we vaccinate during pregnancy, the antibodies produced by the mother cross the placenta and are transferred to the baby, who can thus be protected during the first months of his life,” underlines Ms.me fell.
The Dr Brown estimates that of his pregnant patients, 50 to 60 percent are vaccinated and 40 percent don’t want to be. “Some are antivax convinced ; others have agreed to receive the influenza and whooping cough vaccines that are recommended during pregnancy, but they consider mRNA vaccines too new, but are considering getting vaccinated after their pregnancy. »
With the collaboration of Marie-Eve Cousineau