That's a difficult one for me. I think it would be ok but I am not a doctor and I have no experience whatsoever with IVF.
Even with oral care products you would not really ingest any neem, but you may swallow traces and traces of the ingredients may also be absorbed through the lining of the mouth and the gums. You would absorb more than people do when using skin care products or during use of neem spray in the garden. Still, we are only talking about traces.
Usually traces are nothing to worry about, but as I said, I know nothing about IVF.
You should definitely talk to your doctor about that and get his opinion.
I also think, if it is possible for you to switch to other products for the time being, why risk it?
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