The claim that younger age at marriage (late teens to early 20s) causally increases divorce risk was debunked by two relatively recent studies.

Older papers were confounded: the increased risk is caused by "unobserved factors" such as the innate traits of those who typically marry young today (impulsive, low IQ, low SES, etc.).

The 2021 paper found that young midnight marriages induced by the Vietnam war were actually slightly less likely to divorce. This is not necessarily a universal trend, just evidence that young marriage per se does not cause an increased risk of divorce.

Neither paper looked specifically at very young teen marriages, but I think we can conclude that normal* young people from age 18-25 can safely marry without increased risk of divorce.

* "Normal" defined vaguely as "not retarded, mentally unstable, impulsive, etc."

#fertility