The CA delivery is significantly increased to PR-rich reproductive tissues (uterus and ovaries) over untargeted controls (ND-C5-COOH) at 6 (a) and 24 (b) hours. At both times, the biodistribution of ND-ProGlo (ND-PG) appears consistent with that of ProGlo, indicating that ProGlo is released effectively after injection of ND-PG. Conversely, the control complex, ND-C5-COOH, is cleared rapidly through the kidneys with little remaining at 24 hours.