​Hyperemesis gravidarum is an extreme form of morning sickness, one that made pregnancy a challenging affair for Ms J.

Ms J, 31, an administrative assistant, first started experiencing symptoms such as fatigue, nausea, vomiting and loss of appetite six weeks into her pregnancy. The symptoms persisted during the day and became so severe that they upset her daily routine. Once, she was unable to stop throwing up for 15 minutes.

She could not go to work or get out of the house, and was even hospitalised. “With such severe symptoms, I couldn't function normally. I couldn't work, meet my friends or go out. My social life was affected. I was also always tired and could not concentrate," she said.

Ms J was diagnosed with the condition at KK Women's and Children's Hospital (KKH) and hospitalised for three days. She was given a strong dose of anti-vomiting medication.

Not all pregnant women are hit so hard by morning sickness

Although most pregnant women experience some form of morning sickness, Ms J's case is quite rare. Only a small fraction of women experience such severe morning sickness. Most have mild symptoms that go away after the first trimester.

Ms L, 25, an administrative executive and mother of a five-year-old girl, is one of those lucky ones. She gave birth to her second child, a baby boy, in August 2013.

During her first pregnancy, she vomited about three times during her first trimester but had no other symptoms. During her second one, she had no appetite throughout the first trimester, but did not vomit. She coped by eating small snacks or meals.

Dr Hong Sze Ching, Visiting Consultant at the Department of Obstetrics and Gynaecology, KK Women's & Children's Hospital (KKH), a member of the SingHealth group, explained that morning sickness, which is nausea and vomiting in pregnancy, is very common in the early weeks of pregnancy.

Click here to find out about the causes and symptoms of morning sickness, and tips on how to cope with it.

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