I had a difficult start to my pregnancy - very heavy bleeding (like a heavy period) about the time AF was due but was notified by my IVF clinic that I was indeed pregnant with low progesterone. Another blood test a week later showed the pregnancy was viable. I had slight bleeding again a few weeks later but was advised by my doctor that everything was fine and was probably caused by what I had suspected - having sex! Your cervix becomes soft and blood vessels are more engorged so light bleeding can occur. I know of two friends that this has also happened to. Just take it easy and try not to worry even though I know how hard that can be. The main advice is if the bleeding continues and there is accompanying pain then consult your doctor.
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