What are the possible causes of mild hyperemesis gravidarum? Mild hyperemesis gravidarum (HG) is a condition characterized by nausea and vomiting during pregnancy. While the exact cause of HG is unknown, it is thought to be related to the high levels of hormones present during pregnancy. These hormones, particularly human chorionic gonadotropin (hCG), stimulate the … Continue reading mild hyperemesis gravidarum