There is limited available data addressing whether inactivated COVID-19 vaccination before conception is associated with adverse neonatal outcomes. This cohort study included all singleton live births at our center from March 1 to June 30, 2022. According to whether a maternal inactivated COVID-19 vaccination had been administered within 3 months before conception or not, neonates were identified as being in the vaccinated or unvaccinated group. Vaccination information and clinical characteristics were extracted for analysis. Furthermore, neonatal outcomes were analyzed and compared between these two groups in the present study. The cohort included 856 eligible newborns, of whom 369 were exposed to maternal vaccination before conception and 487 were unexposed newborns. No differences were observed in rates of preterm birth, newborns being small for gestational age, or neonatal intensive care unit admission between exposed and unexposed newborns. Furthermore, even after adjusting for social–economic status and maternal characteristics, there remained no significant differences in these neonatal outcomes. Our study revealed no statistically significant differences between newborns born to women who received inactivated vaccines prior to conception compared with those who did not receive any vaccinations. In addition, our study also highlights the importance of considering COVID-19 vaccination before conception.