oooh, sounds promising, even for those who are already preggers!
Brewed as a tea, red raspberry leaf is one of the safest and commonly used tonic herbs for women wanting to get pregnant or for women who are already pregnant. Red Raspberry Leaf (Rubus idaeus) tones the uterus, improves contractions and decreases constipation. It also contains many vitamins and minerals, including vitamin C and calcium. The alkaloid fragrine is thought to help tone the uterus.
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As always, check with your physician before starting such a regimen. It is generally thought that red raspberry leaf tea should be safe during pregnancy. However, there is some belief that red raspberry leaf can cause minor spotting in the beginning of a pregnancy. Contact your physician for more information.