What is hyperemesis gravidarum?

How does hyperemesis gravidarum differ from morning sickness?

Hyperemesis Gravidarum is a severe form of nausea and vomiting that occurs as early as four weeks of pregnancy and can extend to 10 or 12 weeks or even beyond. The symptoms are much worse than typical morning sickness.

What are the key symptoms?

The majority of pregnant women will suffer from morning sickness during pregnancy. Typically, short episodes of nausea and vomiting occur. Morning sickness can feel severe, but there is a difference between having one bad day of morning sickness when pregnant and having hyperemesis gravidarum. With morning sickness, little if any weight is lost. Nausea and vomiting can cause discomfort and misery but it is infrequent and does not interfere with the ability to eat or drink enough each day.

In hyperemesis, severe nausea and vomiting extend throughout the day, along with the inability to keep food and fluids down. Weight loss (5% or more of pre-pregnancy weight) can be experienced, along with dehydration, lethargy, low blood pressure and a build up of toxins in the blood called ketones. These toxins also appear in the urine, a condition called ketosis. This collection of symptoms when unmanaged appropriately may lead to depression.

How rare is it?

Around 50% of pregnant women will experience nausea and vomiting. However hyperemesis only affects around 1% of pregnancies.

Can it harm the baby at all?

The controlled form of hyperemesis is unlikely to put the baby at any increased risk, as the pregnant woman’s body adapts in favour of the welfare of the pregnancy. However there is evidence to suggest that dehydration, ketone production, malnutrition, and rapid weight loss may lead to low birth weight and smaller babies.

How can expectant mothers ease their symptoms to help minimise the impact in their lives?

While dietary and/or lifestyle changes are enough to help relieve morning sickness, hyperemesis will usually require fluid hydration through a vein and/or medications to stop the vomiting. Breaking the vicious circle of nausea and vomiting improves the recovery and could help prevent, or control, progression to hyperemesis.

With limited evidence and the variable response of individuals to different strategies, it is difficult to give precise guidance to control hyperemesis. In general small frequent meals that are high in carbohydrates and low in fat are recommended. Taking enough time to get up slowly in the morning, eating dry toast or biscuits and plain, cold meals can sometimes help. Ensure adequate hydration by sipping fluids little and often rather than in large amounts. And avoid exposure to spices, greasy foods, strong flavours and meals that give off smells, including hot meals. It helps if someone else can cook for you! Distraction is a good technique, as focusing on the nausea will make the vicious cycle difficult to break.

If symptoms of hyperemesis are suspected then early medical advice should be sought to prevent progress and complications.