hiya, my daughter was stillborn @ 28 weeks. We had to register her, but as far as i remember we got a stillborn certificate, not a birth and death certificate. if a baby is born before 24 weeks, no registering is needed (if they werre dead. If they showed signs of life (no matter what gestation), they will have a birth and death certificate.
Regarding terms, foetus is not the right term for a 28 week gestation baby. They are a baby, whether they lived independently outside the womb or not. A baby born dead before 24 weeks is referred to officially as a late miscarriage, although because they are fully formed, many parents don't like that term