IVF in Belgium as an overseas patient

I think only a hospital could answer you this question. The IVF cost will differ from patient to patient anyway as there are different types of IVF and I imagine the drugs will be tailored towards each patient. The best starting point must be surely finding a few hospitals where the IVF progam is well established.

If the US national is an overseas patient, might she also have some health insurance that might cover this procedure?