I have decided to have a home birth this time (my fourth), and I have had a series of problems with my OBs. I am very healthy, 42, and had vaginal borths with no complications, augementation, etc. The doctor I knew well is ill and not seeing patients, and I was transferred to someone new in the practice. When I told her that I wanted a home birth, she was amenable to being my back-up OB. At my 36 week visit today, she told me she could not be my back-up (or, as she put it, "supervise midwives") because the legal department of the hospital would not let her, nor did she feel comfortable with the idea because of concerns for postpartum hemmorhage. From the little bit of looking I have been able to do today, it seems that PPH is most associated with common obstetric practices in the second stage of labor (induction, instrumental delivery, use of oxytocin) that would not be part of a home birth. She also said that uterine atony increases with each birth, but from what I read, PPH does not have a significant correlation with grand multiparity. Furthermore, I couldn't find a study that rates of PPH comparing normal births in hopsitals versus home births. Seems like a lot of rationalization rather than good science.
In a word, "yup," and you are quite correct that typical hospital management tends to increase the risk of excessive bleeding.
In any case, midwives can treat excessive bleeding at home in the same ways it would be done in the hospital: with meds and massaging the uterus. As I have said before, the urgent problems that may occur at the time of birth can be treated or stabilized for hospital transport by a home birth attendant with the appropriate skills, easily portable equipment, and the proper meds. And, of course, these problems will occur more rarely in women and babies not subjected to the harms of conventional hospital practices and policies.