Technically you can still eat lunch meat, just make sure you know who's making the sandwich, like you don't want meat that has been sitting out for a long time. The concern with lunch meat is that if it's allowed to sit out, it can grow bacteria which can be harmful to you/the baby since your immune system is already lowered due to being pregnant. Ultimately warmed meat is better since it heats/kills the bacteria. But I still make sandwiches with cold meat at home since I know it's properly refrigerated and stored.