It’s an article from a magazine for general readership …
What is the problem with the content of the article? Because you are complaining about the format and not the actual issue at hand?
Now it probably assumed a general knowledge of America’s federal system which it seems you do
not understand (it’s for an American readership, it’s not a direct criticism of you).
In short: twenty or so years ago, CDC updated death certificates to include a pregnancy checkbox that would be ticked if the deceased had been pregnant in the last 42 days.
The idea is that pregnancy can exacerbate medical conditions, so it would include those deaths as well as the more commonly understand deaths from preeclampsia and hemorrhage.
As more and more states used the new CDC forms, more deaths became classified this way.
Once you use more restricted measurements, America’s rate is in line with other developed countries.
Just a glance at the data should
tell this exact story: the very year the CDC released the new death certificates is the year maternal deaths in the USA started to rise and decouple from Western norms.
So America’s way of counting maternal deaths is an overcount, or other developed countries are undercounting, because they fail to see pregnancy or recent pregnancy as an exacerbating factor.
(come to think of it, this was a huge issue with Covid as well)