Ay mama, congrats on your pregnancy! I'd really suggest asking your OB about this one kasi bawat pregnancy ay different, at mas safe talaga na ma-confirm niya kung okay lang yung light grinding sa inyo, some mums sa circle ko were told to avoid it during the first trimester to be extra cautious, but talaga talaga depende sa situation mo. Better to be sure, no? Keep safe and take care of yourself!