Raspberry leaf is the dried leaf of the red raspberry plant, taken as a herbal food supplement, most famously during pregnancy. Traditional use holds that it tones the smooth muscle of the uterus, preparing it for labour, and settles morning sickness, and it is usually drunk as a tea in the later months of pregnancy. The leaves contain tannins, flavonoids, and the alkaloid fragrine, which is credited with the uterine effect. Scientific evidence is thin: small studies suggest it may slightly shorten labour, but data are too limited for firm claims, and because it may stimulate uterine contractions it is generally advised only after the first trimester and with a midwife’s knowledge. It is not recommended for women with complicated pregnancies.