I am not a doctor, nor do I play one on TV, but, having faced this question two times over the last 4 years I would pose these questions:
1. Have any of your relatives suffered from Leukemia?
2. Same for your husband?
3. Any History of other blood disorders, etc on either side?
If no, you can probably safely donate it.
If yes, you may want to discuss this very extensively with a pediatrician or other specialist before making any decisions.
My father, however, has suffered from Non-Hodgkins Lymphoma, which is a disease that can currently be treated with stem cells.