I've used pregnancy tea and/or red raspberry leaf tea throughout all of my pgs

. It's benefits will depend on what herbs it contains.
Mine is:
Red Raspberry Leaf- tones the uterus
Spearmint- flavor and tummy soother
Nettle- helps prevent water retention/swelling
Alfalfa- high in minerals including iron
Oatstraw- high in calcium and calming (I drink it before bed because it's a bit too calming, lol)
Rosehips- high in vit C which helps absorb iron
Fennel- helps with digestion and gas
Lemongrass- flavor
Of course all the benefits are theoretical...I don't know if it helps or not but I enjoy the tea and if nothing else it helps me stay hydrated
I sweeten mine with raw honey or stevia extract powder.