Figure 1. Schematic design of the experimental procedure.

In the control group, the animals were constantly kept under normoxic conditions. In the double-hit groups, dams were exposed to hypoxia from day E14 to E18. After birth, the animals were kept in hyperoxia from day P1 to P14. The experimental double-hit group was given 2 x 10⁵ umbilical cord blood MNCs intraperitoneally. The double-hit control was sham treated, being given 0.9% NaCl solution.