It's pretty short sighted, not to mention extremely callous, to consign a BABY to a lifetime of unnecessary pain and mobility issues to protect other people from a virus that is of negligible risk to the baby
I agree services need to be up and running again, depending on local risk levels in hospitals.
But it's a false dichotomy: save baby, save Covid-19 patient.
The baby could have got Covid-19 by going to hospital for the scan or the parent could, if Covid-19 was rampant in hospitals/through community transmission which it threatened to be.
Now we understand the risk better, and Covid-free zones are established in hospitals, this risk is lower and of course it is right time-dependent services should be up and running again, hopefully in time for this baby.
If NHS services HAD been overwhelmed, and it does seem that the NHS couldn't treat corona and routine problems all at the same time, then how would this have helped this particular baby.
I've suggested some practical steps the OP can take, so have others, I think that's more productive than arguing about a lockdown which even if entirely lifted, won't get the OP what she wants in the time-frame she needs it.