This kind of thing is best discussed as a list with bullet points, so here goes:If you feel, at any point during your labor, that something is not right and you feel the desire to be in hospital, listem to your intuition regardless of what your midwife says. Fever can indicate an infection. Sudden blood loss before delivery can indicate a placental abruption. This means your placenta has started to separate from the uterine wall, which leaves the baby without oxygen. Heavy blood loss following delivery means hemorrhage. It is possible to bleed out within five minutes, so it requires prompt medical care and sometimes a blood transfusion. Many midwives do carry Pitocin to treat hemorrhage, but that is something best discussed before your birth. Fetal distress is determined, among other things, through an irregular heartbeat which can be heart on the doppler or fetoscope. Meconium in the amniotic fluid can likewise indicate fetal distress. Waters being broken for over 24 increases the risk of infection. A labor that just will not progress may well require transfer. A umbilical cord coming out before the baby is highly dangerous, and requires immediate delivery or transfer.
Not all of these situations are easily resolved at home, and some, like cord prolapse, are very dangerous in any birth setting. Transferring doesn't always get you out of danger. And this is not a complete list; there may be other situations that require transfer too. This list only relates to birth. Many newborn situations also require transfer.