Raspberry leaf tea is not strictly a tea, it's a herbal infusion, but it comes in a tea bag and I pour hot water over it to drink it so I'm calling it a tea.
People have been drinking it for years, actually centuries, for it's pregnancy and labour benefits. I'm drinking it purely because of it's deliciousness not because I need assistance with my non-existent pregnancy but it can also reportedly help with easing the PMS crazies and oddly enough diarrhoea.
At the moment I'm drinking this one which has a couple other ingredients added to up the deliciousness.