Is implantation bleeding worse when you're anemic?

No difference: There is no difference in implantation bleeding if you are anemic or normal blood count. It is important to have a good hematocrit prior to and during pregnancy. The baby will steal hemoglobin from the mom. That is one reason it is important to be on vitamins with iron prior to pregnancy. The other reason is that having an adequate amount of Folic Acid can reduce the rate of spina bifida.