Generally, yes, you can go on a cruise during your first trimester, as most cruise lines allow pregnant passengers to sail up to their 24th week of pregnancy. However, the first trimester brings specific challenges like morning sickness, which can be significantly exacerbated by the motion of the ship. It is crucial to consult your OB-GYN before booking to ensure there are no complications. You should also check the specific "Fit to Travel" policy of your cruise line, as many require a doctor's letter stating your due date and that you are in good health. Additionally, consider the medical facilities on board; while ships have infirmaries, they are not equipped for prenatal emergencies or neonatal care. Traveling to remote ports might also limit your access to specialized hospitals, so choosing an itinerary with reliable land-based medical infrastructure is a wise precaution for peace of mind.