Can only a OB to blood test to test hgc levels? If not who else?

Can only a OB do my blood work to see if my hgc is going up like it should. I havnt event seen an OB yet (I plan to use the same one I did with my daughter) and he won't see you untill 10 weeks. I went to a pregnancy clinic that set me up at ultra sound at 7 weeks but they don't do blood work.