24/09/2014 10:45 BST | Updated 20/05/2015 10:12 BST

What Is Hyperemesis Gravidarum?


What is hyperemesis gravidarum?

Hyperemesis gravidarum (HG) is a condition which affects roughly one in 100 pregnant women. Symptoms include prolonged and repeated nausea and vomiting, inability to keep down food and/or liquid, fatigue and low blood pressure. Often conflated with morning sickness, it is in fact far more severe, usually requiring at least one admission to hospital. Imagine having severe food poisoning 24 hours a day, seven days a week. That's what HG can feel like. At a time when you're meant to be excited about your pregancy, you feel the worst you've ever felt.

The Duchess of Cambridge is reported to be suffering from hyperemesis gravidarum during her second pregnancy, as she did while pregnant with Prince George.

Jane Eyre author Charlotte Brontë died during pregnancy after suffering prolonged periods of nausea, and some biographers believe it was dehydration and malnutrition related to the condition that killed her. What causes hypermesis gravidarum?

Frustratingly, we don't know exactly. Historically, morning sickness and HG were considered to be psychological - as late as 2003, some researchers were still claiming that it was mostly in the mind. The most common explanation is that morning sickness and HG are the product of the hormonal changes which accompany pregnancy.

Isn't it just bad morning sickness?

No, HG differs from run-of-the-mill morning sickness, whether mild or severe, in many notable ways.

Both conditions have symptoms in common, but with HG they present in a much more extreme way. For instance, the nausea associated with morning sickness is far more severe for women experiencing HG, and can easily lead to serious dehydration or nutritional problems requiring periods of hospitalisation. Women suffering HG can lose as much as one-tenth of their body weight and are at risk of experiencing the symptoms of starvation.

Fatigue is also much more severe, and can be totally debilitating for weeks or months, leaving sufferers unable to complete day to day tasks.

When your 'morning sickness' symptoms are impacting on your ability to live a normal life, you may be experiencing HG, and should speak to your GP or midwife as soon as possible.

The story continues after this video.

What can I do to cope with HG?

One important thing is to avoid sensations which trigger feelings of nausea. Some of them are predictable, like the smells of certain foods (fried food is a common offender), but others are less obvious - all kinds of sensations, from lights to motion to sounds, can be triggers for certain women. Learn what yours are as soon as possible and make sure those around you help avoid them.

If you're having trouble keeping food and drink down, the Pregnancy Sickness Support charity has a list of foods considered the most palatable for HG sufferers, as well as tips for getting the most nutrients out of a restricted diet.

Be aware of the signs of dehydration (dark urine or low volume of urine). Suck on ice cubes or sip water from a straw if you are having trouble keeping liquids down. If you can't stomach water, try juice, tea, Lucozade or lemonade - any liquid helps. If this doesn't work, you may need to go to hospital to be rehydrated via an intravenous drip.

Above all, don't suffer in silence if your symptoms are making you miserable - see a doctor before they become dangerous.

If I have HG with my first pregnancy, will I have it with the next one?

Not necessarily. But studies have shown that, like the Duchess of Cambridge, women who experience HG in their first pregnancy have a higher chance of suffering again during subsequent pregnancies.

The best thing you can do is to be prepared for the worst case scenario. Apply what you learnt during your last pregnancy to make the best possible plans for your childcare, work schedule, and help with household tasks. This will make the (hopefully unlikely) scenario of another case of hypermesis gravidarum easier to cope with.