Oh Ernest don't worry! There was a bit of unrest in Rome for that football fan that was accidentally shot in a motorway caff, nothing terribly serious.
? don't know how long you've been in CH but I wonder if a lot of the negativity about this move stems from not really wanting to uproot again. Would you have felt the same about going to France or Germany? Re the not knowing the language I'd see that as a bit of a challenge in a positive sense, but then I'm a linguist by training.
Just think of the positive aspects, you and your DCs will be learning a new language, exposed to a new culture, eating decent food and possibly getting to meet interesting people. Nothing ventured nothing gained and all that, it's worth giving it a go, at least you'll have another experience under your belt. And remember, Italy is not the third world - well, maybe some parts appear to be at times, but certainly not Milan. Keep an open mind, who knows you might end up really loving it. FWIW the idea of moving to oh so perfect Switzerland gives me goosebumps, so it works both ways.
Italy is very good for antenatal care. You can of course go private but I used the public health system and it was very good, much better than the UK if my sister's experiences are anything to go by. Maybe not as good as the Swiss system but not at all bad considering the problems in the public health services. The best maternity hospital is in Milan (Mangiagalli) or if you're after a more natural approach there is the Buzzi or a midwife centre at Sesto. All have private wings too. Mat leave is heaps better than the UK but if you're not working that's no use to you. Once the baby's born you get assigned a paediatrician, plus you can choose a private one if you prefer (I personally don't see the point but many do). There are no HVs as such but there are drop in centres called consultaori pediatrici where you can get baby weighed, go for bfeeding advice and do things like baby amssage and such, all free of charge. Here in Italy they're very pro bfeeding and seem to be less ill-informed than in the UK so you'll get loads of help if you need it. Less hung up abut it to judging from what I read on here....
Re SJH school, I should imagine your ds3 would be classed as reception, they seem to follow the UK system exactly, it's not an international school and Italian is just another lesson as far as I could see. I thought of sending DD there, she'll be 3 this summer, so eligible for Italian materna which is the equivalent of preschool at the SJH. Have you seen their website? There is all the information you could desire and more. here it is.
Goodness me, I've written an essay of epic proportions!