Fair point longtime!
wish I had had all my kids in Belgium at those rates, but I suppose I would also have shed out a fair few euro in medical costs too.
Ok, so you are not obliged to join a mutuelle but you can do, if paying uk NI, but you can do if you want to. You apply for form S1 from HMRC in Benton Park, Newcastle who issue this form to UK ordinary residents temporarily working in the EU but continuing to pay UK NI contributions. We pay UK NI and Belgian SS too in our family, every year dh has to re-apply for this form and this year it took 4 months to come, then he hands it to the mutuelle who then treat him as if he is paying Belgian SS and he has the same refund and credit rights with the mutuelle. Sorry if this sounds complicated, it's not really that bad, worth it as a family for what we gain.
It costs us 108 euro for the year to be in a mutuelle and we claim back over twice that amount every year, as you get "credits" for sports activities the children and we do - it's a way of encouraging good health and avoiding having to pay out for ill health that they subsidise "good" activities, so even in this respect it is worth joining a mutuelle. For us another benefit is that the mutuelle covers by far the greatest costs of speech therapy for our daughter, it gives us significant reductions on sports "stages" for our children, full mutuelle refunds on dental check-ups, GP visit for 5 euro (after mutuelle refund), daughter broke her arm recently and the total bill for 2 hospital visits for cast and cast removal was just 10 euro (after mutuelle refund), access to cheap emergency care for children, if they ever fall sick and I have to still go to work. Dh's UK employer used to oblige him and us to be mutuelle members, as they do not cover us under private health insurance, but now they no longer oblige dh to pay to be in a mutuelle, he still remains part of a mutuelle because of the positive benefits. It's probably not at all high on list of priorities, when pregnant and having just moved country, but may be worth considering.
Anyway, I'm sure some nice mumsnetters or other mums will end up helping you out. Good luck.