Yes, folks outside the US, we here in America try to time pregnancies over bullshit details of how our insurance plans work. At least anyone who's thought about it does. Those who haven't get a nasty surprise, and pay (up to) double.
Agreed. Also, being born even on December 31 2019 qualifies you for having another dependent in your household for the entire 2019 taxes, so it's a double whammy.
A due date after September-ish ensures you're only paying the medical treatments/screens/hospitalization/etc for that year and that year only (vs, as you mention, a due date that happens potentially anytime between Jan-August).
It's tricky. Unfortunately.
And almost everyone where some medical professional, somewhere in the chain of hospital visits, happened to be out of network - someone you had no idea would be involved. Examples would be where the doctor sent lab results to another doctor for analysis, etc.