To anyone who has not been pregnant – or lived with someone who has been pregnant – I have to tell you that the term morning sickness is somewhat misguiding. About 80% of all pregnant ladies complain of morning sickness, but for most this nausea lingers the whole day and doesn’t lift until the 14th week of pregnancy. The constant pang of nausea is unsettling and if you add vomiting to the equation, day-to-day life is simply exhausting.The most likely cause of morning sickness is the body reacting to the pregnancy hormone, human chorionic gonadotropin (hCG). This is the hormone that is detected on a pregnancy test.