For all those that are wondering, diaphragmatic hernias actually can be diagnosed prenatally. They are detected on the routine ultrasound that is offered to all pregnant women. In some cases, they can even operate before the baby is born to repair one! I agree that having a baby with a diaphragmatic hernia is a very good reason not to have a homebirth. And even if someone were unlucky enough to have a baby with an undiagnosed diphragmatic hernia, it is unlikely it would have been diagnosed and x-rayed in 10 minutes - the 10-minute Apgar score hasn't even been completed at that point.
Positive airway pressure, using a bag valve and mask, is readily available in the home setting, and all reputable independent midwives carry resuscitation equipment and portable oxygen with them. While it may not look like the fancy equipment in hospital, it is the same and does the same job.
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