How long have you been without your period? My understanding is that you need to be period free for one full year to be certain that you are through with them.. I have never heard of soy products inducing a period. I think returning to soy will not have any affect on your period.. but as always check with your physician when in doubt... a quick phone call to the office might relieve your doubts.

Soy and other phytoestrogens are 1000 times weaker than real human estrogen. I tried them for a year and they did nothing for my symptoms. I think your hot flashes stopped because your body was making more estrogen for a while. There are a lot of ups and downs during peri.

I haven't been period free for a year, and I did notice a definate difference when I took the soy. Maybe it's just different for different folks?