Morning sickness is usually about vomiting and nausea. The symptoms are worst in the early hours of the morning and subside over the course of the day. Many pregnant women are experiencing morning sickness any time of the day and sometimes lasts all day long. It can start as soon as you get pregnant and may continue until the 4th month of pregnancy.
Morning sickness is caused by low blood sugar, hormonal changes, emotional stress, fatigue, increased estrogen and progesterone levels and sensitivity to smell. It is believed that morning sickness is a defense mechanism that protects the developing baby against toxins ingested by the mother.