The way I see it is hospital birth and vaccination are both interventions pushed by mainstream medicine as being for the 'greater good', in that none of us know what the future holds (illness, complications at birth etc) so let's take a preventative step by birthing with a medical team, in a hospital setting, and then vaccinate the child 'just in case' (hep b is a true indication of this, since few newborns use needles or have sex, but they can be exposed to heb b in a hospital setting and vaxxing at birth ticks the box of having 'fixed that')
Those that are anti vax and home birth generally subscribe to a philosophy of trust in the bodies ability to both birth and the child's protect itself from illness. They see interventions as actually prohibitive to optimal health and care, and question the expectation we, as consumers, should just accept the info given to us by mainstream medicine. Most research the issues thoroughly and come up with their own health care model (birth with midwives, delayed or partial vax, optimal food for health and nutrition, long term breastfeeding etc).
Even discussions about best outcomes for the baby often negate the mothers wishes and bodily autonomy. Trust that no mother wants to put her child in harm, but we should not assume that the baby's needs are of greater importance than the mothers bodily rights.
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