Roanna I wrote a long post the other night on your exact theme but it got lost. I think I posted that to me menstrual blood felt darker, possessive and maybe fresh blood was lighter and brighter somehow. I'd be really interested to know what kinds of spells you would use menstrual blood for vs fresh blood. I was thinking about menstrual blood for a protection spell for a child but actually I wondered would it be too suffocating or possessive - the worst sort of protective mothering IYSWIM. I could imagine using it to bind someone sexually or fascinate them sexually (I know this is a common use). Could also imagine it to protect my home or individual objects. This is just instinct though.
I would probably use fresh blood to protect a child. I don't feel like I know enough about blood magic yet to throw myself in. If you can recommend any good reading I'd be grateful.