Hi mama! I haven't heard of longan causing spotting myself, and a few of us mums have eaten it throughout pregnancy without issues, pero any spotting during pregnancy is something you really should mention to your OB as soon as you can, kahit konti lang, para sure lang. Spotting can be from so many things (stress, cervical irritation, etc.) and not necessarily from the fruit, so don't panic but do get it checked out para peace of mind mo. Ingat always!