Posted on by Dr. Francis Collins
Clinical trials have shown that COVID-19 vaccines are remarkably effective in protecting those age 12 and up against infection by the coronavirus SARS-CoV-2. The expectation was that they would work just as well to protect pregnant women. But because pregnant women were excluded from the initial clinical trials, hard data on their safety and efficacy in this important group has been limited.
So, I’m pleased to report results from two new studies showing that the two COVID-19 mRNA vaccines now available in the United States appear to be completely safe for pregnant women. The women had good responses to the vaccines, producing needed levels of neutralizing antibodies and immune cells known as memory T cells, which may offer more lasting protection. The research also indicates that the vaccines might offer protection to infants born to vaccinated mothers.
In one study, published in JAMA , an NIH-supported team led by Dan Barouch, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, wanted to learn whether vaccines would protect mother and baby. To find out, they enrolled 103 women, aged 18 to 45, who chose to get either the Pfizer/BioNTech or Moderna mRNA vaccines from December 2020 through March 2021.
The sample included 30 pregnant women,16 women who were breastfeeding, and 57 women who were neither pregnant nor breastfeeding. Pregnant women in the study got their first dose of vaccine during any trimester, although most got their shots in the second or third trimester. Overall, the vaccine was well tolerated, although some women in each group developed a transient fever after the second vaccine dose, a common side effect in all groups that have been studied.
After vaccination, women in all groups produced antibodies against SARS-CoV-2. Importantly, those antibodies neutralized SARS-CoV-2 variants of concern. The researchers also found those antibodies in infant cord blood and breast milk, suggesting that they were passed on to afford some protection to infants early in life.
The other NIH-supported study, published in the journal Obstetrics & Gynecology, was conducted by a team led by Jeffery Goldstein, Northwestern’s Feinberg School of Medicine, Chicago . To explore any possible safety concerns for pregnant women, the team took a first look for any negative effects of vaccination on the placenta, the vital organ that sustains the fetus during gestation.
The researchers detected no signs that the vaccines led to any unexpected damage to the placenta in this study, which included 84 women who received COVID-19 mRNA vaccines during pregnancy, most in the third trimester. As in the other study, the team found that vaccinated pregnant women showed a robust response to the vaccine, producing needed levels of neutralizing antibodies.
Overall, both studies show that COVID-19 mRNA vaccines are safe and effective in pregnancy, with the potential to benefit both mother and baby. Pregnant women also are more likely than women who aren’t pregnant to become severely ill should they become infected with this devastating coronavirus . While pregnant women are urged to consult with their obstetrician about vaccination, growing evidence suggests that the best way for women during pregnancy or while breastfeeding to protect themselves and their families against COVID-19 is to roll up their sleeves and get either one of the mRNA vaccines now authorized for emergency use.
 Immunogenicity of COVID-19 mRNA vaccines in pregnant and lactating women. Collier AY, McMahan K, Yu J, Tostanoski LH, Aguayo R, Ansel J, Chandrashekar A, Patel S, Apraku Bondzie E, Sellers D, Barrett J, Sanborn O, Wan H, Chang A, Anioke T, Nkolola J, Bradshaw C, Jacob-Dolan C, Feldman J, Gebre M, Borducchi EN, Liu J, Schmidt AG, Suscovich T, Linde C, Alter G, Hacker MR, Barouch DH. JAMA. 2021 May 13.
 Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination in pregnancy: Measures of immunity and placental histopathology. Shanes ED, Otero S, Mithal LB, Mupanomunda CA, Miller ES, Goldstein JA. Obstet Gynecol. 2021 May 11.
 COVID-19 vaccines while pregnant or breastfeeding. Centers for Disease Control and Prevention.
COVID-19 Research (NIH)
Barouch Laboratory (Beth Israel Deaconess Medical Center and Harvard Medical School, Boston)
Jeffery Goldstein (Northwestern University Feinberg School of Medicine, Chicago)
NIH Support: National Institute of Allergy and Infectious Diseases; National Cancer Institute, National Institute of Child Health and Human Development; National Center for Advancing Translational Sciences; National Institute of Biomedical Imaging and Bioengineering
Posted on by Dr. Francis Collins
It’s natural and highly appropriate for women to be concerned about their health and the wellbeing of their unborn babies during pregnancy. With the outbreak of the pandemic, those concerns have only increased, especially after a study found last spring that about 30 percent of pregnant women who become infected with SARS-CoV-2, the coronavirus that causes COVID-19, needed to be hospitalized .
But that early study didn’t clearly divide out hospitalizations that were due to pregnancy from those owing to complications of COVID-19. Now, a large, observational study has taken a more comprehensive look at the issue and published some reassuring news for parents-to-be: the vast majority of women who test positive for COVID-19 during their pregnancies won’t develop serious health complications . What’s more, it’s also unlikely that their newborns will become infected with SARS-CoV-2.
The findings reported in JAMA Network Open come from a busy prenatal clinic that serves women who are medically indigent at Parkland Health and Hospital System, affiliated with the University of Texas Southwestern, Dallas. Researchers there, led by obstetrician Emily Adhikari, followed more than 3,300 pregnant women, most of whom were Hispanic (75 percent) or African American (14 percent). From March through August of this year, 252 women tested positive for COVID-19 during their pregnancies.
At diagnosis, 95 percent were asymptomatic or had only mild symptoms. Only 13 of the 252 COVID-19-positive women (5 percent) in the study developed severe or critical pneumonia, including just six with no or mild symptoms initially. Only 14 women (6 percent) were admitted to the hospital for management of their COVID-19 pneumonia, and all survived.
By comparing mothers with and without COVID-19 during pregnancy, the researchers found there was no increase in adverse pregnancy-related outcomes. Overall, women with COVID-19 during pregnancy were not more likely to give birth early on average. They weren’t at increased risk of dangerous preeclampsia, a pregnancy complication characterized by high blood pressure and organ damage, or an emergency C-section to protect the baby.
The researchers found no evidence that the placenta was compromised in any way by the SARS-CoV-2 infection. In most cases, newborns didn’t get sick. Only 6 of 188 infants (3 percent) tested positive for COVID-19. Most of those infected were born to mothers who were asymptomatic or had only mild illness.
This is all encouraging news. However, it is worth noting that mothers who developed severe COVID-19 before reaching 37 weeks, or well into the third trimester of pregnancy, were more likely to give birth prematurely. More research is needed, but the study also suggests that diabetes may increase the risk for severe COVID-19 in pregnancy.
This study’s bottom line is that most women who become infected with SARS-CoV-2 during pregnancy will do just fine. That doesn’t mean, however, that anyone should take this situation casually. The finding that 5 percent of pregnant women may become severely ill is still cause for concern. Plus not all researchers come to the same conclusion—an update to the first study cited in this post recently found a greater risk for pregnant women becoming severely ill from COVID-19 and giving birth prematurely.
Taken together, while there’s no need to panic about COVID-19 infection during pregnancy, it’s still a good idea for pregnant women and their loved ones to take extra precautions to protect their health. And, of course, follow the three W’s: Wear a mask, Watch your distance, and Wash your hands.
 Characteristics of women of reproductive age with laboratory-confirmed SARS-CoV-2 infection by pregnancy status—United States, January 22–June 7, 2020. CDC COVID-19 Response Team. MMWR Morb Mortal Wkly Rep. 2020 Mar 27;69(12):343-346.
 Pregnancy outcomes among women with and without severe acute respiratory syndrome coronavirus 2 infection. Adhikari EH, Moreno W, Zofkie AC, MacDonald L, McIntire DD, Collins RRJ, Spong CY. JAMA Netw Open. 2020 Nov 2;3(11):e2029256.
Coronavirus (COVID) (NIH)
Combat COVID (U.S. Department of Health and Human Services, Washington, D.C.)
Data on COVID-19 during Pregnancy: Severity of Maternal Illness (Centers for Disease Control and Prevent, Atlanta)
Emily Adhikari (University of Texas Southwestern Medical Center, Dallas)
Posted on by Dr. Francis Collins
It’s well known that preeclampsia, a condition characterized by a progressive rise in a pregnant woman’s blood pressure and appearance of protein in the urine, can have negative, even life-threatening impacts on the health of both mother and baby. Now, NIH-funded researchers have documented that preeclampsia is also taking a very high toll on our nation’s economic well-being. In fact, their calculations show that, in 2012 alone, preeclampsia-related care cost the U.S. health care system more than $2 billion.
These findings are especially noteworthy because preeclampsia rates in the United States have been steadily rising over the past 30 years, fueled in part by increases in average maternal age and weight. This highlights the urgent need for more research to develop new and more effective strategies to protect the health of all mothers and their babies.