Virus World

Infants born to people who had COVID while pregnant are at a higher risk of respiratory distress, but vaccination greatly lowers the risk. More than four years after the virus that causes COVID first appeared, scientists continue to discover new ways that the illness threatens pregnant people and babies—as well as additional evidence that vaccination offers significant protection. A new study finds that babies born to women who got COVID while they were pregnant were three times more likely to develop serious breathing problems than infants whose mothers didn’t have the disease during pregnancy, even if the infants weren’t infected themselves. Seventeen percent of the babies in the study who were exposed to COVID before birth developed respiratory distress, compared with only about 5 to 6 percent of newborns in the general population before the pandemic. The findings were published on Wednesday in Nature Communications....

Stucy cited (Jan. 24, 2023):

https://doi.org/10.1038/s41467-023-44549-5 

BACKGROUND

Many pregnant persons in the United States are receiving messenger RNA (mRNA) coronavirus disease 2019 (Covid-19) vaccines, but data are limited on their safety in pregnancy.

METHODS

From December 14, 2020, to February 28, 2021, we used data from the “v-safe after vaccination health checker” surveillance system, the v-safe pregnancy registry, and the Vaccine Adverse Event Reporting System (VAERS) to characterize the initial safety of mRNA Covid-19 vaccines in pregnant persons.

RESULTS

A total of 35,691 v-safe participants 16 to 54 years of age identified as pregnant. Injection-site pain was reported more frequently among pregnant persons than among nonpregnant women, whereas headache, myalgia, chills, and fever were reported less frequently. Among 3958 participants enrolled in the v-safe pregnancy registry, 827 had a completed pregnancy, of which 115 (13.9%) resulted in a pregnancy loss and 712 (86.1%) resulted in a live birth (mostly among participants with vaccination in the third trimester). Adverse neonatal outcomes included preterm birth (in 9.4%) and small size for gestational age (in 3.2%); no neonatal deaths were reported. Although not directly comparable, calculated proportions of adverse pregnancy and neonatal outcomes in persons vaccinated against Covid-19 who had a completed pregnancy were similar to incidences reported in studies involving pregnant women that were conducted before the Covid-19 pandemic. Among 221 pregnancy-related adverse events reported to the VAERS, the most frequently reported event was spontaneous abortion (46 cases).

CONCLUSIONS

Preliminary findings did not show obvious safety signals among pregnant persons who received mRNA Covid-19 vaccines. However, more longitudinal follow-up, including follow-up of large numbers of women vaccinated earlier in pregnancy, is necessary to inform maternal, pregnancy, and infant outcomes.

Published in NEJM (June 17, 2021):

https://doi.org/10.1056/NEJMoa2104983 

See also NEJM (June 17, 2021):

https://doi.org/10.1056/NEJMe2107070 

Pregnant women with severe and critical COVID-19 had rapid improvement in their heart and lung function along with decreased inflammation when given inhaled nitric oxide gas, a new Massachusetts General Hospital study shows.  “We noted rapid relief from breathlessness in these patients, with lower respiratory rate and better oxygenation after mask administration of high concentration nitric oxide, with no adverse side effects,” said Dr. Lorenzo Berra, investigator in the department of anesthesia, critical care and pain medicine at MGH. Nitric oxide, known for saving the lives of oxygen-starved newborns, was given to six pregnant coronavirus patients at MGH at a high dosage for 30-60 minutes, twice a day, for a total of 39 treatments.  The patients were severe — all six needed supplemental oxygen, four were treated in the ICU and two were intubated, according to the study in Obstetrics & Gynecology.

They remain susceptible to the virus for longer after the first vaccination, but achieve a mostly normal response after the second, a study says.  Pregnant and breastfeeding women respond to the first dose of the coronavirus vaccines more slowly than other women, and mount a less potent defense against the virus, according to a new study. After the second dose, however, their response looks almost normal. The results, published this month in the journal Science Translational Medicine, suggest that pregnant and breastfeeding women remain susceptible to the virus for longer after vaccination. The study underscores the importance of giving these women the second dose in time, and monitoring them closely in the meantime for signs of infection. During pregnancy, the immune system is modified to tolerate the fetus — effectively a foreign entity — leaving pregnant women particularly susceptible to pathogens like the coronavirus. Because of this, pregnant women are more likely to become severely ill and to die from Covid than other women of the same age.

New study bolsters the case for vaccinating pregnant women.  Since the start of the coronavirus pandemic, it has become increasingly clear that COVID-19 hits pregnant women harder than the general population. Now, one of the first large studies with a proper control group has firmed up earlier evidence for how the virus can alter the course of pregnancy and harm mothers and their newborns. The study of more than 2100 pregnant women enrolled at hospitals in 18 countries found that, compared with uninfected pregnant women, those with COVID-19 are at higher risk for severe illness, death, pregnancy complications, and preterm birth. Those results underscore the importance of including pregnant women in priority groups for COVID-19 vaccines and limiting their exposure to ill people, says corresponding author Aris Papageorghiou, a fetal medicine specialist at the University of Oxford.  “This is a great study,” says physician, epidemiologist, and public health specialist Nathalie Auger of the University of Montreal Hospital Research Centre, who was not involved with the research. “They followed women through pregnancy, which is a really great design, and helped confirm the previous studies that are much easier to critique.”

Many studies have linked pregnancy to worse COVID-19 outcomes, but they have either included too few participants to draw firm conclusions, or have relied on health records that women agree to share after the fact. These registries tend to lack details such as when in pregnancy a woman got infected. They also attract sicker patients, which could make the effects of COVID-19 look worse than they actually are. Such studies also often compare the outcomes for infected women with those for women who gave birth before the pandemic. This lack of a contemporary control group means researchers aren’t getting a realistic picture of the risks to uninfected women who gave birth after COVID-19 had upended global health care systems. To avoid such biases, the new study enrolled women at any stage of pregnancy who received care at 43 medical centers, from Russia to India to Brazil, between March and October 2020. For each infected woman, the researchers immediately enrolled two pregnant women at the same hospital and same stage of pregnancy without a known infection. They then followed both groups of women—706 with a COVID-19 infection and 1424 without—through their babies’ deliveries and after discharge from the hospital. Clear differences emerged between the two groups. Those with COVID-19 had a 76% greater chance of pregnancy-induced high blood pressure, known as preeclampsia or eclampsia. They were three times as likely to have a severe infection and five times as likely to be admitted to an intensive care unit, Papageorghiou’s team reports today in JAMA Pediatrics. Eleven women with COVID-19 died, compared with just one woman in the uninfected group.

The study also linked COVID-19 to a 60% to 97% increased rate of preterm birth, and— in infected women with a fever and shortness of breath—to a fivefold increase in neonatal complications such as immature lungs, brain damage, and eye disorders. About 13% of babies tested positive for the virus, and cesarean delivery was linked to a higher risk of transmission. Breastfeeding didn’t appear to transmit the virus—a small bit of good news. The risk estimates are roughly in line with what other studies have found, Papageorghiou says, including a recently published study that looked at health records for more than 400,000 U.S. pregnant women, nearly 6400 with COVID-19. The new study helps makes the case for offering all pregnant women COVID-19 vaccines, Papageorghiou says. “We believe pregnancy itself [puts women into] a sufficiently high-risk group,” he says. In the United States, the Centers for Disease Control and Prevention (CDC) includes pregnancy under high-risk medical conditions with priority for vaccines, but not all states have included pregnancy in priority groups. In the United Kingdom, pregnant women were only recently added to such groups. Because the approved vaccines were not tested in pregnant women, some health authorities are hesitant to prioritize them for vaccination—despite reassurances from obstetrics experts that the shots appear safe in this group. Preliminary evidence published yesterday in The New England Journal of Medicine supports this view. Using data from a CDC reporting system, researchers found no obvious safety problems in more than 800 U.S. women who gave birth after receiving messenger RNA vaccines in December 2020, January, and February. The higher rates of preterm birth found in the study are especially relevant in lower income countries, where health care systems are less able to care for premature infants, Papageorghiou adds. “The challenge will be much more severe in those settings.”

Findings Published in JAMA Pediatrics (April 22, 2021):

https://doi.org/10.1001/jamapediatrics.2021.1050 

The Pfizer/BioNTech and Moderna Covid-19 vaccines are effective in pregnant and lactating women, who can pass protective antibodies to newborns, according to research published Thursday in the American Journal of Obstetrics and Gynecology. Researchers at Massachusetts General Hospital, Brigham and Women's Hospital and the Ragon Institute of MGH, MIT and Harvard looked at 131 women who received either the Pfizer/BioNTech or Moderna Covid-19 vaccine. Among the participants, 84 were pregnant, 31 were lactating and 16 were not pregnant. Samples were collected between December 17, 2020 and March 2, 2021.  The vaccine-induced antibody levels were equivalent in pregnant and lactating women, compared to non-pregnant women. The antibody levels were "strikingly higher" than those resulting from coronavirus infection during pregnancy, the team noted. "These vaccines seem to work incredibly effectively in these women," said one of the researchers, Galit Alter, a professor of medicine at the Ragon Institute.

Pregnant women with COVID-19 are at greater risk for hospitalization, ICU admission and receipt of mechanical ventilation compared with nonpregnant women of the same age, according to findings published in MMWR. In addition, Hispanic and non-Hispanic Black women who are pregnant are disproportionately impacted by SARS-CoV-2 infection during pregnancy, the findings demonstrate.

“During pregnancy, women experience immunologic and physiologic changes that could increase their risk for more severe illness from respiratory infections,” Sascha Ellington, PhD, of the CDC’s COVID-19 Emergency Response Team, and colleagues wrote. “To date, data to assess the prevalence and severity of COVID-19 among pregnant U.S. women and determine whether signs and symptoms differ among pregnant and nonpregnant women are limited.” Between Jan. 22 and June 7, CDC received reports of 326,335 women of reproductive age (15 to 44 years) who had positive test results for SARS-CoV-2. Of the 91,412 (28%) women with laboratory-confirmed infections for whom data on pregnancy status were available, 8,207 (9%) were pregnant. While symptomatic pregnant and nonpregnant women with COVID-19 reported comparable rates of cough (more than 50%) and shortness of breath (30%), pregnant women reported headache, muscle aches, fever, chills and diarrhea less often. Additionally, among women with COVID-19, 31.5% of pregnant women were reported to have been hospitalized compared with 5.8% of nonpregnant women. After adjusting for age, the presence of underlying medical conditions and race/ethnicity, pregnant women were significantly more likely to be admitted to the ICU (adjusted RR = 1.5, 95% CI, 1.2-1.8) and receive mechanical ventilation (aRR = 1.7, 95% CI, 1.2-2.4). According to the study results, 16 (0.2%) COVID-19-related deaths were reported among pregnant women aged 15 to 44 years and 208 (0.2%) such deaths were reported among nonpregnant women (aRR = 0.9, 95% CI, 0.5-1.5).

“Pregnant women might be at increased risk for severe COVID-19 illness,” the authors wrote. “To reduce severe COVID-19-associated illness, pregnant women should be aware of their potential risk for severe COVID-19 illness. Prevention of COVID-19 should be emphasized for pregnant women and potential barriers to adherence to these measures need to be addressed.”