As shown in Figure 3, we found that the H63D mutation in the HFE gene was significantly more prevalent among women from Stratum 2 (initial Hb levels > 130 g/L) who developed iron overload, compared with women who completed the pregnancy without risk of hemoconcentration (41.4% and 19.8%, respectively, p = 0.045). The gene discussed is HFE; the disease is Tangier disease.