Yes and cause uterine contractions. I did find one bumpie that said this as well:
"First, it's Red Raspberry leaf that is the active ingredient in the tea. It
tastes like black tea (not fruity) & in medicinal
amounts/concentrations it is not recommended until after 37 weeks. It
tones the uterus to make labor pains more effective in dilating the
cervix for delivery.
I took it starting at 38 weeks pregnant. One
tea bag steeped in 8 oz. of boiling water for 15 minutes. You drink
five, 8 oz. cups per day until labor starts. I had DD at 39 weeks. My
labor was 12 hours total.
I cannot advise taking it while TTC. It
can inhibit your uterine lining & cause contractions or preterm
labor/miscarriage if taken early in pregnancy. Some women start it
during 2nd trimester, but my midwife advised against it.
you take any sort of medication or herbal remedy you should consult your
doctor about what it could mean for your individual situation. "
If you're having hormonal issues, JJ or OP, talk to your doctor. You shouldn't go off and self-dx. You can end up causing more harm than good. Also, the saying "don't fix it if it ain't broke" definitely applies to your body.
Remember, there is a lot of misinformation out there. Just take a look at the site that T3's sister was referring her to. They'll tell you whatever they can to sell their products. That doesn't make it true.