Ok so I'm on my 2nd cycle of trying out soy isoflavones (thought I'd give things a little boost) my cycles are usually 27/28 days long. On my first cycle of trying these my cycle only lasted 25 days, however I am now on my 29th day of my current cycle with no af as of yet. I've had mild hot lower crampy back pains on and off during the week but nothing so far. Also had a headache on and off for a few days. I have a feeling that I might have messed my cycle up taking these. I did a test just now with a bfn so makes me think my cycles have been messed up forgot to mention I usually ovulate around days 12/14 no later however I didn't check the last two months on the soy.