There are many reasons to believe that the American and the “girl” in Ernest Hemingway’s “Hills Like White Elephants” are married. Their conflict is about her having the baby, not about getting married. The subject of marriage never comes up. But in the 1920s the girl would not want to have the baby without being married. The American actually tells her five times that she can go ahead and have the baby if it is important to her--although he makes it obvious that he doesn’t want to get tied down to domesticity and a steady job. He knows intuitively that when a couple has a baby it changes their whole life; whereas the girl knows intuitively that love-making is intended for procreation and not just for fun and games. The labels on their luggage show they have been traveling all over Europe together. It would have been difficult for an unmarried couple to share the same hotel room in the 1920s. In some countries it may have even been illegal. People could register as Mr. and Mrs., but they would have to turn over their passports each time they registered, and it would be obvious if they were not married.
Hemingway based many of his short stories on personal experience. He wrote about some things as a sort of confession to free himself from his guilty feelings. He and Hadley, his first wife, had actually had a baby they called Bumby a few years before Hemingway published “Hills Like White Elephants” (Gertrude Stein and Alice B. Toklas were his godparents); the story could have been written long before Hemingway managed to get it accepted for publication. It seems extremely likely that he was recalling his mixed feelings when Hadley told him she was pregnant. If there had been a conflict over the issue at that time, apparently it was Hadley who had prevailed. Hemingway, however, did not adapt well to fatherhood and domesticity. He and Hadley were divorced in January 1927, when Bumby was only about three years old.
Also, Hemingway does not explain that the couple in “Hills Like White Elephants” are married because he was trying to avoid exposition almost entirely. His next short story, “The Killers,” is written in a similar objective style. Hemingway at that time was trying to see how much he could “leave out” of a story in order to focus on drama. One of his many biographers, A. E. Hotchner, quotes him as saying:
I guess I left as much out of "The Killers" as any story I ever wrote. Left out the whole city of Chicago.
And in The Green Hills of Africa (1935), Hemingway expressed his now-famous “iceberg” theory:
If a writer of prose knows enough of what he is writing about he may omit things that he knows and the reader, if the writer is writing truly enough, will have a feeling of those things as strongly as though the writer had stated them. The dignity of movement of an ice-berg is due to only one-eighth of it being above water. A writer who omits things because he does not know them only makes hollow places in his writing.