Abstract
Aim SARS-CoV-2 infection is associated with an increased risk of preterm birth, preeclampsia and stillbirth. Therefore, women planning pregnancy during the pandemic should have been recommended to be vaccinated against COVID-19. The objective of this study was to evaluate the impact of pre-pregnancy and asymptomatic COVID-19 infection during pregnancy, as well as vaccination, on preterm birth during the pandemic.
Material and Method This retrospective study included clinical records of women vaccinated before pregnancy. All women were SARS-Cov-2 PCR-negative at the time of birth and did not have a history of PCR-confirmed COVID-19. The asymptomatic transmission of COVID-19 was determined by the presence of antibodies to the N-antigen (N+S+), the presence of vaccination was determined by anamnesis and confirmed by the presence of antibodies only to the S-antigen (N-S+).
Results From 113 vaccinated women with no history of PCR-confirmed COVID-19, 46 (40%) had antibodies to the N antigen of SARS-Cov-2. Preterm birth was significantly more common in women over 40 years of age (p=0.005), with preeclampsia (p=0.006) and with intrauterine growth retardation (p=0.016). To assess the impact of vaccination, 2 study groups (1 - those who had COVID-19 asymptomatically or in an unexpressed form and 2 - those who were vaccinated against COVID-19 and did not have the disease) were formed. No significant differences were found between groups in terms of the incidence of premature births (43% and 37%, respectively, p>0.05).
Conclusions Maternal Covid-19 vaccination carried out before pregnancy did not have any negative effect on the premature birth rates.