Pregnancy Outcomes in Patients After Completion of the mRNA Coronavirus Disease 2019 (COVID-19) Vaccination Series Compared With Unvaccinated Patients.

OBJECTIVE: To compare frequency of perinatal death between pregnant patients who completed the mRNA coronavirus disease 2019 (COVID-19) vaccination series and unvaccinated patients. METHODS: This retrospective cohort study included 15,865 pregnant patients who delivered 16,132 newborns after 20 weeks of gestation within a large regional health system between January 1, 2021, and December 31, 2021. Patients who received two doses of mRNA vaccine (Pfizer-BioNTech [BNT162b2] or Moderna [mRNA-1273]) were included in the vaccinated group and were compared with unvaccinated patients. Exclusions included partial vaccination, viral-vector vaccine, major congenital anomalies, and higher-order multiple gestation. Our primary outcome was perinatal death, including stillbirth and neonatal death, which was evaluated by logistic regression. Unadjusted odds ratios and adjusted odds ratios (aORs) were reported, controlling for age, body mass index (BMI), diabetes, hypertension, smoking, twin gestation, and insurance status. Propensity score matching was also performed. RESULTS: A total of 15,865 patients were included in the final analysis: 2,069 in the vaccination group and 13,796 in the control group. Only 13.0% of the cohort was included in the vaccination group; however, the vaccination rate increased over the course of the study period as the vaccine became more widely available and accepted. Vaccinated patients were older, with higher rates of people of non-Black racial non-Hispanic ethnic backgrounds, people with private insurance, and those with higher BMIs. Vaccination was associated with a lower incidence of perinatal death (0.5% vaccinated group vs 0.8% unvaccinated group, aOR 0.20 0.05-0.88). Vaccination against COVID-19 was also associated with lower rates of preterm delivery (aOR 0.63, 0.48-0.82), neonates with very low birth weight (aOR 0.35, 0.15-0.84), and neonatal intensive care unit (NICU) admission (aOR 0.66, 0.52-0.85). The association between vaccination and lower rates of perinatal death was no longer significant after propensity score matching. CONCLUSION: In a large retrospective cohort study, receipt of the primary mRNA COVID-19 vaccination series was associated with a lower rate of several adverse pregnancy outcomes, including perinatal death, preterm delivery, neonates with very low birth weight, and NICU admission. Although the decreased rates of perinatal death did not remain significant after propensity score matching, there was evidence of directional benefit for vaccinated patients.

Safety-Related Outcomes of Novel mRNA COVID-19 Vaccines in Pregnancy.

OBJECTIVE: The objective of this study was to describe the safety profile and demographic data for a cohort of pregnant individuals who received an mRNA coronavirus disease 2019 (COVID-19) vaccine. STUDY DESIGN: Prospective cohort study (with exposure matching) of individuals with active pregnancy who underwent immunization with a novel mRNA COVID-19 vaccine matched 1:2 with vaccinated age-matched female nonregnant controls was carried out. The primary outcome was defined as any vaccine-related complaints as defined in the original safety data. Secondary outcomes included specific complaints, COVID-19 screening test, and positive COVID-19 test. RESULTS: Eighty-three vaccinated pregnant persons were age-matched with 166 female controls, all of whom were vaccinated between December 2020 and January, 2021. There was no difference in race or ethnicity between the groups. The mean body mass index of pregnant patients was lower than that of controls (26.1 vs. 29.2, p = 0.002). The frequency of complaints following vaccine administration was not different between pregnant and nonpregnant patients (18.1 vs. 16.9%, p = 0.201). Pregnant individuals were more likely to report fever (4.8 vs. 0.6%, p = 0.044) and gastrointestinal symptoms (4.8 vs. 0%, p = 0.012). CONCLUSIONS: Side effect profiles of COVID-19 vaccine administration at our institution were relatively similar between pregnant and nonpregnant individuals and no serious complications occurred in either group. As COVID-19 infection in pregnancy can have significant morbidity, our data support the continued use of the vaccine for pregnant patients. KEY POINTS: · Pregnant and nonpregnant women had a similar frequency of complaints.. · No serious adverse outcomes were observed in either group.. · Pregnant women were more likely to report fever and gastrointestinal side effects which may reflect gestationally mediated physiological responses to immunization..