What are the considerations to bring 4-5 month old baby for travel? To winter country? Is it a risk that baby will find it too cold?

I will go to more develop countries with medical facilities just in case of emergencies. If you're travelling to winter countries just make sure you buy warm clothings for your baby like winter overalls, beanie, gloves. It may be quite difficult to find infant sizes here, so you can consider buying them online from us or UK - carters, oshkosh, gymboree, next etc.