New data that is reassuring for COVID-19 vaccination in pregnancy

One of the largest reports of COVID-19 vaccination in pregnancy supports evidence that it is safe, although the authors say more extensive research is needed.

The preliminary results are based on reports of more than 35,000 American women who received the Moderna or Pfizer injection during pregnancy. The rates of miscarriages, premature births and other complications were comparable to those in published reports of pregnant women before the pandemic.

The new evidence from researchers at the federal Centers for Disease Control and Prevention was published Wednesday in the New England Journal of Medicine.

None of the women involved received the Johnson & Johnson one-time vaccine, which became available after the study, and is now in limbo as US authorities investigate reports of blood clots in a handful of women.

Separately, the American Society for Reproductive Medicine approved vaccination during pregnancy on Tuesday, based on evidence it has been evaluating for more than a year.

Everyone, including pregnant women and those trying to conceive, should get a COVID-19 vaccine. The vaccines are safe and effective, ”the association said in a statement.

A representative of the society said the group has not evaluated the latest evidence about Johnson & Johnson’s vaccine.

A representative from the American College of Obstetricians and Gynecologists said the CDC report is promising, but that longer-term follow-up is needed. That group has previously said that vaccination against COVID-19 should be available to pregnant women and those who are breastfeeding, and many pregnant American women have chosen to get vaccinated.

Although pregnant women were excluded from studies leading to emergency licensing of the vaccines, evidence showed no harm in women who were unknowingly pregnant when they enrolled.

Dr. Laura Riley, chair of the ob-gyn at Weill Cornell Medicine in New York, said the new results are reassuring.

“It’s great to have data to share with our patients who continue to weigh the risks and benefits of vaccination,” she said. “They know the potential complications of COVID infection in pregnancy and now there is some safety data on human pregnancies.”

Pregnant women who become infected with the coronavirus are at an increased risk of complications, including hospitalization in the intensive care unit, premature birth and death.

The authors of the study, led by Dr. The CDC’s Tom Shimabukuro said continued monitoring and more evidence is needed, including for women who receive COVID-19 vaccinations in the early stages of pregnancy.

Their research included information on 35,691 pregnant American women enrolled in a voluntary smartphone-based vaccination surveillance scheme and who received Moderna or Pfizer vaccines between mid-December 2020 and the end of February.

It also included pregnancy complication reports from nearly 4,000 women enrolled in a US vaccine safety registry. Of these, 86% or 712 resulted in a live birth, mostly among women vaccinated in the third trimester.

Most women in the surveillance group reported injection site pain, but more severe reactions were less common. Pregnant women seemed more prone to injection site pain with both vaccines, but were less likely to have different reactions than non-pregnant women.

In the vaccine registry, about 13% of pregnant women reported miscarriages, less than 1% stillbirths, 9% premature births and 2% birth defects. Those rates are all within the same range seen in pre-pandemic pregnant women reports.


Follow AP Medical Writer Lindsey Tanner at @LindseyTanner.


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