Red raspberry tea not til 36 weeks???

I wanted to start drinking raspberry leaf tea so I asked my midwife about it and she said they don't recommend starting rinking it until 36 weeks. (???!) I've always heard as soon as you're in the 3rd tri, it's fine (and have heard some midwives even recommend it halfway through 2nd tri). My pregnancy is 100% low risk as of now at 33w3d. I know I should have asked her why but I was just too surprised lol. So has anyone else been told to wait that long, and do you know of any possible reasoning for this? I'm confused about the waiting since I know it can't cause preterm labor.