Maz, this is my third prg. With my first I had spotting on and off from 4 weeks until about 12 weeks and then again in the second and third tri's once or twice (usually after BDing) and I now have a perfectly healthy DD who is 2.
My second prg I had no spotting at all until 12 weeks, it was dark brown and got progressively heavier. I had a missed m/c.
This prg, I had no bleeding until 9 weeks, when i had one day of light pinkish coloured spotting, and am now 18 weeks, no spotting since.
So for me, my pregnancies where i had spotting have resulted in healthy babies (well so far) and the one I didn't have any spotting ended in heartbreak.
Bleeding in early prg is totally normal and definately does not always lead to m/c.
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