[chimeracoder]

> TLDR, maternal morbidity in US sources often widens the net to include things like drug overdoses.

The article doesn't mention drug overdoses specifically, though it does mention cancer as a common cause not related to pregnancy that is increasing maternal death rates.

Ironically, drug overdoses are themselves subject to this same issue: many of the officially-reported stats for both hospitalizations and deaths due to drugs use a method that is essentially equivalent to "did this person report having taken a substance" (or "were traces of a substance detected"), regardless of the amount taken or the cause of death, which means that those are overestimated as well.