surfsteve wrote:http://www.herbwisdom.com/herb-evening-primrose.html
By interfering with the production of inflammatory prostaglandins released during menstruation, the GLA in evening primrose oil can help to lessen menstrual cramps. It may also minimise premenstrual breast tenderness, irritable bowel flare-ups, and carbohydrate cravings, and help to control endometriosis-associated inflammation
Evening Primrose Oil (Oenothera Biennis)This is a different species of Oenothera than the one this thread is about. It's hard to say to what degree Oenothera speciosa shares properties with Oenothera biennis. The color of their flowers is different and their growth habit is also different, but regarding their biochemical properties I have no information.