I want to delay the cutting of my umbilical cord

Okay, so I'm going to ask my doctor to add to my birth that I don't want the umbilical cord cut for the first 5 minutes after birth. I've been studying a lot and the placenta still pulses and pumps blood through the cord for at least 3 to 5 minutes after birth. I want my son to receive the full benefits of his cord blood, and it also helps prevent newborn anemia and iron deficiency later in babies life. My youngest struggles with anemia and I can't help but think that if they hadn't cut his cord AS SOON as he slid out simply because she had another delivery to attend to he wouldn't have this problem possibly. Maybe he wouldn't maybe he would. I still want the choice to not cut so soon. Anyone else delaying the cutting of the umbilical cord?