This is something I have thought about a lot actually...not that I have come to any solid conclusions! I will say this--there are times I hear birth stories wherein the mom is blaming the mw for contributing to trauma, and I can see it. Mostly this has to do with the mw's approach to her power in the situation--there are times when mws do things, or fail to do things, based on their sense of authority in the matter of birth. For instance, insisting on things like AROM, or a certain pushing position, insisting on transport or on staying home when the mom wants to transport. This can lead to a woman's sense of having been betrayed and ripped off by her mw instead of supported and respected.
Then again, I hear some stories where it is not nearly so clear as all that, not at all. The only clear 'fact' seems to be that the mom does feel traumatized--but it is not so clear that the mw could have done anything any differently under the circumstances, or indeed may have actually gone above and beyond the call of duty and respect and putting her own neck on the line. Well, things *always* 'could be done differently' in any situation--just trying to convey that it appears that there is no 'reason' to blame the mw--she probably did as much, and as respectfully, as anyone could have.
Pregnancy and birth are such huge things in our lives. Women come into pregnancy with a whole universe of self...beliefs, state of health and habits, expectations, psychology/personality, support system/culture, personal history, a relationship with self and to personal power...and all of that helps to make up her 'experience' of pregnancy and birth; it all plays out in her experiences. It has been said that experience is not just what happens to you--it is what you DO with what happens to you. And I see this so intimately with the women I work with--and of course, through my own pregnancies/births. Perception really does seem to be everything here. Memory can be quite selective, and highly biased in the face of strong emotions, and in the presence of certain personality traits and/or cultures and support systems! That selectivity can definitely be both for better OR for worse: I remember my own labors as gorgeous, luscious, blissful empowering events, surrounded by loving friends, that resulted in a BABY!!!!!--even the long ones that hurt like hell for hours on end...my memory selects the wonder and tends to delete the pain. Another woman has a highly painful labor, and *her* memory is of trauma and pain, tending to delete the support, the power, the bliss, the victory.... We are all different in the way we process things, what we expect, how we name things...and so forth.
I believe generally that every person present in any moment is co-creating events...that we are all responsible for things that happen around us to some degree. Whenever I have received criticism from clients (or from my kids, or anyone, really), I have to take it seriously: both as 'their own truth' and as something that somehow is part of my truth--and I have to give it real consideration. Granted, sometimes what I wish I'd done differently was not to work with a given family--had seen signs I ignored that did speak earlier to me about the possibility that no matter what happened, she and/or her mate would not be happy with the birth or with me! But then there are times when I have learned valuable things about how better to serve families at such an important time...had things brought into my awareness that I had not thought about before, did not see in myself, but could see through client feedback were not contributing to my manifestation of my ideal as a mw.
Anyway. IMO, this is a crazy and very intense time of upheaval in human consciousness. The 'old rules'--of marriage and family, of relationships to authority and power, especially--are no longer in play for many...but we do not have any 'new rules' set up to play by. Not to mention 'overcrowding psychosis', so much suffering on the planet, so much movement/transience of communities, ever greater financial disparities, more and more kinds and instances of abuse between humans...there is a lot going on AND, we are generally ever so much more aware than ever before of all that is going on (whether we watch the TV news or not). I definitely can't say that I mourn the 'old rules and norms'--and have hopes that we as a species are in the midst of a very positive change for ourselves and all of life ultimately. However--all this chaos does take its toll in the meantime. Gestating and birthing women ARE more sensitive to input, words, vibes, etc, anyway--and now, we don't have the comfort of traditions and interpersonal expectations to lean on. Also, homebirth (and any non-conventional birth such as birth center birth) unfortunately represents a deviation from the norm that takes a lot of courage and steadfastness in this era (at least in the US)--there is a huge amount of inherent stress upon families and mws alike, at a time when life is far better served by everyone being relaxed, and mothers feeling safe!
Anyway--I sum up this ramble by saying that while I do think it is possible for mws to contribute to a woman's sense of having been traumatized, it is far from a simple question, with no simple answers. I can take responsibility enough to try to look honestly and humbly at any negative feedback I might receive after a birth...try to see where my changes would help me to be a better servant of women/families at such a precious, important time. And I can't take responsibility for another's unspoken and unmet expectations, the fact that she might be an abuse survivor who is acting out her past victimization now, or the way their family might put pressure on a mom to assay blame upon me, or a baby's position that might have led to a very painful labor, and so forth. I am only human, and have only so much control over events. I believe in taking responsbility, yes...but to take too much responsibility for events or for another's feelings/experience is only another way of making oneself, as care provider, the One with All The Power. And there is no situation, no relationship, in which I have that much power!