However the midwife visited this morning, and told us that the warning does include the sleepyhead and that she really has to advise us against using it
Firstly, the press release involving sleep positioners is advice given in USA, not UK.
UK advice on Safe Sleep has not changed in any way. The safest possible place for your baby to sleep is on a seperate, flat mattress. If you wish to cosleep theŕe are safer ways to do this:
www.lullabytrust.org.uk/safer-sleep-advice/co-sleeping/
While the sleepyhead (and any similar product) is not considered the "safest" option, they are also not specifically labelled "unsafe" either.
It is true that cosleeping (even when following safety guidelines) is also not the "safest" option either. So you appreciate there that you make an informed, educated decision based on your view of risk management. Some people are more risk averse than others.
The same is true with any of these types of products, including the Sleepyhead. It is unhelpful and just burying your head in the sand to assume the sleepyhead carries no risk. It does have a risk. The safest possible place for your baby to sleep is a firm, flat, waterproof mattress seperate to you and clear of all pillows, toys or loose bedding. Anything else isn't "safest". But that does not automatically make them "unsafe", according to the UK SIDS advice.