Turned

1911
Charlotte Perkins Gilman
Turned
B-

The "wife" and the "other woman" team up when the latter, a naive 18-year-old Swedish housemaid, becomes pregnant by the husband.  I find it a bit implausible that he's away on business for months at a time, but it does give the wife a chance to mull things over.  Points for Mrs. Marroner having a Ph.D.

The story reminds me a bit of Lummox by Fannie Hurst, where the title character was a pregnant Scandinavian maid.  I used to own it but I think I got rid of it years ago because it was too depressing.  This has a more upbeat, though still dramatic, ending.