ACOG (American College of Obstetricians and Gynecologists) strongly recommends that all pregnant and recently pregnant people receive the COVID booster once they are eligible (6 months after Pfizer/Moderna or 2 months after Johnson & Johnson). You can choose any of the vaccines for your booster and do not need to choose the same vaccine that you originally received.
For more information, please see https://www.acog.org/womens-health/faqs/coronavirus-covid-19-pregnancy-and-breastfeeding.