Oxygen affinity of hemoglobin in postmenopausal women

In a group of 12 postmenopausal women the P50-value (i.e. half saturation tension of oxygen) and other parameters of the red blood count were determined and compared with values of a male group of the same age. A small but significant difference could be found between the hematocrit values but no other values differed. In particular, the sex difference in oxygen affinity reported earlier does not exist in men and women on this age group.