Laura,
Hair loss is listed as a symptom of hypothyroid.  I don't know why your
endo told you it was unrelated.  I have had the problem too and told it
was thyroid related.  Synthroid (according to their insert) can cause
hair loss in the first few months of use.  I think it even can happen
when doseage is changed (happens to me).  Your hair loss could also be
related to pregnancy because they do say that happens after you have a
baby.

Good luck, Pam H.