Just a little point - as early as 1971, most school districts in the US had rules in place forbidding girls from being expelled for being pregnant. These rules included making sure the young woman in question was able to stay in regular classes if circumstances allowed. (IE, she could get to class regularly and didn't have to take a lot of time off so she could work to support herself.)
In many locales only one parent signature is required to allow an underage pregnant girl to get married. (and she can be
very young.)
Otherwise - just like Clark to offer to marry Lois.