Findings that show COVID-19 vaccination during pregnancy improves neonatal outcomes can serve “a critical role” in counseling these patients about the vaccine.
“While I was rotating in the OB/GYN department as an intern, I saw several cases of pregnant individuals with severe COVID-19 who had to give birth during the second trimester,” Atsuyuki Watanabe, MD, explained. “Although the neonates were negative for SARS-CoV-2, they still experienced complications, including respiratory failure and other conditions along with prematurity. Previous studies have also shown that pregnant individuals with COVID-19 can have newborns at higher risk for NICU admission, stillbirth, preterm birth, and other peripartum events compared with those without COVID-19.”
As a result, “we focused on neonatal outcomes as well as maternal outcomes” for a study published in JAMA Pediatrics, Dr. Watanabe noted. Together with Toshiki Kuno, MD, PhD, FESC, FSCAI, Dr. Watanbe and the rest of the study team conducted a systematic review and meta-analysis of nine observational studies. Specific neonatal parameters, including preterm birth, small for gestational age, low Apgar score, NICU admission, and intrauterine fetal death (IFD), served as the primary outcomes, while maternal outcomes served as the secondary outcomes, including SARS-CoV-2 infection, Cesarean delivery, postpartum hemorrhage, and chorioamnionitis.
Vaccination Reduces Risk for Maternal & Neonatal Events
The analysis included 81,349 vaccinated (mean age, 32-35) and 255,346 unvaccinated individuals (mean age, 29.5-33) during pregnancy. Almost all vaccinated individuals (98.2%) received mRNA vaccines.
Six studies described the number of COVID-19 vaccine doses; 52,295 of 61,255 individuals (85.4%) received two doses of mRNA vaccines during pregnancy. Seven studies documented the timing of the first vaccine among 58,548 individuals. Nearly half of all individuals in these studies (N=27,988; 47.8%) received the first vaccine during the third trimester. Slightly fewer received the first injection during the second trimester (N=27,108; 46.3%). The smallest proportion of patients (N=3,452; 5.9%) received the first dose during the first trimester.
“COVID-19 vaccination during pregnancy was associated with lower risks for NICU admission and IFD (Infographic),” Dr. Kuno noted. “This is probably because vaccinated mothers have a lower risk for SARS-CoV-2 infection, and maternal SARS-CoV-2 infection may be a risk factor for worse neonatal outcomes. In addition, COVID-19 vaccination during pregnancy was not associated with higher risks for maternal and neonatal events, such as Cesarean delivery, postpartum hemorrhage, chorioamnionitis, preterm birth, small size for gestational age, and lower Apgar scores.”
Specifically, COVID-19 vaccination in pregnancy was associated with reduced risk for NICU admission (OR, 0.88; 95% CI, 0.80-0.97) and IFD (OR, 0.73; 95% CI, 0.57-0.94). Vaccination was also associated with a decreased risk for maternal SARS-CoV-2 infection (OR, 0.46; 95% CI, 0.22-0.93).
Findings Establish Benefits of Vaccination for Newborns
Drs. Watanabe, Kuno, and colleagues noted the role of the findings in establishing the safety for newborns of COVID-19 vaccination during pregnancy, which could serve “a critical role” in counseling pregnant patients about the teratogenicity of the COVID-19 vaccine.
“COVID-19 vaccination during pregnancy may be associated with better neonatal outcomes without causing noticeable adverse effects,” Dr. Kuno said. “COVID-19 vaccination during pregnancy may not only provide maternal protection against SARS-CoV-2 but may also be associated with better neonatal outcomes. Providers should consider these risk-benefit balances when counseling patients.”
The study results also described maternal protection against SARS-CoV-2 “paramount,” given that most pregnant patients with COVID-19 who required intensive care were not vaccinated.
“Given the promising efficacy of COVID-19 vaccination in preventing maternal SARS-CoV-2 infection and the critical association between COVID-19 and neonatal/maternal outcomes, our findings further underlined the importance of maternal protection against SARS-CoV-2 infection,” the researchers wrote.