Illustration by Anna PariniLike millions of women before me, when I got pregnant I experienced run-of-the-mill so-called morning sickness, a low-level queasiness that persisted throughout the day and then disappeared almost completely after twelve weeks. Why do some women get extra sick during pregnancy? It turns out there’s a name for extreme morning sickness: hyperemesis gravidarum, or H.G., which translates, roughly, to “excessive vomiting during pregnancy.” In my reporting on H.G., for a piece published today, I learned that the illness has a long history. She was unable to eat, or to move without vomiting, and she lost the baby at fifteen weeks.