I've had two children (they are 6 & 7 now) and never experienced this symptom before (guess I never would have known with my second because I was breastfeeding then).  I'm still unsure right now if I'm pregnant, but my nipples have leaked a small amount of milky fluid.   First time I noticed was in hot shower right about time of suspected implantation bleeding.  I've squeezed them a few times since over last week when not in shower and they produce small drop.  Has this ever happened to you? I just turned 40 two weeks ago.