The following hemoglobin (Hb) and Hct levels are classified as anemic: 1st trimester: Hb < 11 g / dL; Hct < 33% 2nd trimester: Hb < 10.5 g / dL; Hct < 32% 3rd trimester: Hb < 11 g / dL; Hct < 33% If Hb is < 11.5 g / dL at the onset of pregnancy, women may be treated prophylactically because subsequent hemodilution usually reduces Hb to < 10 g/dL.