I guess you mean "At what stage is the danger of losing the baby unlikely?"
Don't think that way. The overwhelming majority of babies are born at term and healthy. (But they don't make the medical news.) Enjoy yourself. Shop for your baby whenever you want.
i was shopping for my baby two years before trying to conceive... it helps to buy a little at a time so your not over wheeled once that time comes. 40 weeks goes by pretty quick when your expecting
I was knitting little sweaters and caps. I even made a little coat for it to come home in. And I made batiste shirts and embroidered them. That was for the first baby. By the time the babies started to mount up I was less occupied making things. But for the first one you have all the time in the world. It's lots of fun.