COVID-19 Vaccination During Pregnancy – Short- and Long-Term Outcomes of a Prospective Cohort Study

To examine the effects of COVID-19 vaccination on pregnancy outcomes. This was a prospective observational cohort study of pregnant women targeted via social media platforms. The participants were asked to fill online questionnaires at the baseline, after one month and after one year from recruitment. Pregnancy outcomes were compared between vaccinated women who received COVID-19 vaccine while pregnant, to non-vaccinated women (during or before pregnancy). Our composite primary outcome included one or more of the following: fetal sonographic anomaly, intrauterine growth restriction, vaginal bleeding, hypertensive disorders, gestational diabetes, cervical insufficiency, and preterm birth. Of 1128 recruited women, 194 were excluded due to vaccination before pregnancy. Of the examined cohort of 934 participants, 770 (82%) received vaccination at any time during pregnancy, while 164 (18%) remained vaccine naïve during pregnancy (non-vaccinated group) some of which completed vaccination after delivery. Women in the "vaccinated group" had more risk factors for COVID-19 infection (51% vs. 40%, p=0.007, odds ratio (OR) 1.60, 95% CI 1.13- 2.26) and higher BMI (24.1 ± 4.9 vs 23.0 ±4.0 kg/m2, p=0.012, OR 1.05, 95% CI 1.01-1.10) (Table 1). Composite primary outcome did not differ between the two groups (32% vs 25%, p=0.061, OR 1.74, 95% CI 0.81-3.84), while the risk for COVID-19 infection was significantly lower in the vaccinated group (6.6% vs 24%, p < 0.001, 95% CI 0.14-0.36) (Table 1). Vaccination during pregnancy reduced the incidence of COVID -19 without increasing the rate of obstetric complications.