Immediate medical care IS available at home - home birth isn't something out of the Middle-ages! ;-) MWs are trained experts in child birth and they bring all the same appropriate equipment, drugs and expertise as a hospital midwifery lead unit or a birth centre.
I would state that you get better care at home, you are guaranteed to have at least 1-2-1 care with your MW - they don't leave your home to attend to another labouring women, they keep and eye on you, and only you - and this has been proved to be a significant benefit to birth outcomes whether at home or in hospital, but you are unlikely to get that in hospital, although it is part of every hospitals plan to try and provide this.
Instances of transfer and need for Obstetric care are much lower for home births than compared to similar mums who attend a MLU in hospital, as there isn't a culture of intervention being on-tap as it where and the pressure to deliver in 1 hour of you are a second time mum and 2 hours if it is your first. Failure to progress is the single biggest cited reason for c-sections!
In emergency situations, appropriate measures will be taken with your consent to transfer to a hospital if indicated, and as said by others.. even this takes time even if you are in hospital, they don't have a theatre all set up and a consultant waiting just for you. they still need to book it arrange it and phone it ahead... same at home.
The beauty of home birth, is that you can go into hospital anytime you like - for what ever reason, and women who home birth are appreciative of the medical skill that has been afforded to modern women by obstetric advances in saving lives - but we also understand that for 90% of patients the intervention spiral that is leading the UK and the US to some shocking statistics on c-section rates, is out of kilter with the inherent normalcy of labour and birth for most women. WHO accepts that only 10% of women should have A REAL NEED for c-sections.
For a better birth experience - after all this is something that will effect you for the rest of your life - I would only say to any women make sure you are central and responsible for your own health and make your decisions (whatever they be) based in INFORMED choice and NOT just what someone else recommends because of policy or you think they have some authority over your body because they are a medical professional.
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