Hyperemesis Gravidarum

Nausea and vomiting are incredibly common during pregnancy. But there is a big difference between feeling a bit queasy and being so unwell that you can't eat, drink, work, look after yourself or get through the day. Hyperemesis gravidarum (HG) is the most severe form of pregnancy sickness. It can be physically exhausting, emotionally draining and completely disruptive to everyday life. And despite the rather casual name "morning sickness", this isn't something that necessarily happens in the morning. For some people, the sickness can last throughout the day and night. If you're struggling with severe pregnancy sickness, you deserve proper support and treatment.

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What is Hyperemesis Gravidarum?

 

Hyperemesis gravidarum is severe nausea and vomiting during pregnancy. There isn't one single test that tells you whether you have HG. Healthcare professionals will look at the overall picture, including how much you're vomiting, whether you're able to eat and drink, whether you've lost weight and whether you're becoming dehydrated or unwell.

 

HG can affect around 1 to 3 in every 100 pregnancies. It is more than simply having "really bad morning sickness". The important question is not just: "How many times have you been sick?" It's also: "How much is this stopping you from functioning and looking after yourself?"

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What does Hyperemesis Feel Like?

 

Everyone's experience is different, but HG can involve:

• severe or prolonged nausea

• frequent vomiting

• being unable to keep food or fluids down

• dehydration

• weight loss

• feeling weak, exhausted, dizzy or light-headed

• passing very little urine or having dark-coloured urine

• being unable to carry out normal daily activities

• difficulty working or caring for other children

• feeling isolated or unable to socialise

• significant anxiety or low mood

 

It can have a profound effect on your quality of life. And you don't have to be vomiting every few minutes for your symptoms to deserve attention. Severe nausea, difficulty eating and drinking, and the impact on your ability to function all matter.

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Why Does it Happen?

 

The exact cause of pregnancy sickness and hyperemesis isn't completely understood. Pregnancy hormones are thought to play an important role, and research has identified a hormone called GDF-15, which is produced by the placenta and is associated with nausea, loss of appetite and vomiting during pregnancy. Genetic differences may help explain why some people experience much more severe symptoms than others. 

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You may be more likely to experience HG if:

• you've had it in a previous pregnancy

• you're expecting twins or triplets

• you have a family history of severe pregnancy sickness

 

But it can happen to anyone. It isn't because you haven't tried hard enough to eat well, rest or manage your symptoms.

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Is Hyperemesis Just Really Bad Morning Sickness?

 

Not quite. Pregnancy sickness is very common and usually improves by around 16 to 20 weeks. HG is much more severe and can continue beyond this point. Some people with HG improve during the second trimester. For others, symptoms continue for much longer and may last throughout pregnancy. There is also no requirement for your symptoms to fit a particular timetable before you deserve treatment.

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When Should I Ask for Help?

 

Please don't wait until you are completely exhausted or severely dehydrated before asking for help. Speak to your GP or midwife if your sickness is severe, isn't improving or is stopping you from carrying out normal activities. You should seek medical advice particularly if:

• you cannot keep fluids down

• you're vomiting frequently

• you're losing weight

• you're very thirsty

• you're dizzy or light-headed

• you're passing very little urine

• your urine is very dark

• you're unable to take your usual medication because you cannot keep it down

• your symptoms are having a significant impact on your ability to function

 

The NHS advises contacting your midwife, GP or NHS 111 if you're vomiting and have very dark urine or haven't passed urine for more than 8 hours.  If you're worried about how unwell you are, it's appropriate to ask for an assessment.

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What Happens if I Need to be Assessed?

 

Your healthcare team will usually want to understand:

• how long you've been experiencing symptoms

• how often you're vomiting

• whether you're able to eat and drink

• whether you've lost weight

• whether you've tried any medication

• whether you've had HG before

• whether you have any other symptoms

 

They may check your blood pressure, pulse, temperature, breathing and weight, and assess whether you're dehydrated or undernourished. You may also have urine and blood tests. An ultrasound scan may be offered if you haven't already had one, including to establish how many weeks pregnant you are and whether you're expecting more than one baby.

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Can Hyperemesis be Treated?

 

Yes. There are several anti-sickness medicines that can be used during pregnancy. Sometimes one medication is enough. Sometimes you may need to try different medicines or a combination of treatments to get your symptoms under control. 

 

This is an important one to know: You do not have to prove that your sickness is severe enough before asking about medication. NICE recommends offering anti-sickness medication to pregnant women with nausea and vomiting who choose pharmacological treatment, and considering intravenous fluids for moderate to severe symptoms.  Your healthcare professional can talk you through the benefits and possible side effects of the medication being offered. Some anti-sickness medicines are specifically licensed for use in pregnancy, while others may be prescribed when appropriate based on the available evidence and your individual circumstances.

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What if I Can't Keep Medication Down?

 

If you're unable to keep tablets or fluids down, you may need treatment through an assessment unit or hospital. This might include:

• fluids through a drip to treat dehydration

• anti-sickness medication given through a drip, injection or another route

• thiamine (vitamin B1), particularly if you've been unable to eat normally

• medication to reduce stomach acid where appropriate

• treatment to reduce the risk of blood clots if you're dehydrated and less mobile

 

Many people can receive treatment through an outpatient or day-care service and then go home once they're feeling better. Some people need to be admitted to hospital. 

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Will I Need to go Into Hospital?

 

Not necessarily. Hospital admission may be recommended if you're significantly dehydrated, unable to keep fluids or medication down, have abnormal blood tests or have lost a significant amount of weight. Your healthcare team will assess your individual circumstances and decide what level of treatment you need. And if you've previously needed hospital treatment for HG, it's worth talking to your maternity team early in a subsequent pregnancy so that you can make a plan for what to do if symptoms return.

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What Can I Do at Home?

 

When you're dealing with severe pregnancy sickness, the usual advice to "eat healthily and drink plenty" can feel almost laughable. When you're struggling to keep anything down, getting enough calories and fluids is the priority. Some people find it easier to:

• eat very small amounts frequently

• choose foods that are easier to tolerate

• eat foods that are high in carbohydrate and lower in fat

• choose cold foods if cooking smells are triggering

• avoid foods or smells that make symptoms worse

• sip fluids little and often rather than drinking large amounts at once

• try ginger or acupressure if these feel helpful

 

These strategies can help some people, but they are not a substitute for medical treatment when you have HG.

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What About My Baby?

 

This is understandably one of the biggest worries. Mild to moderate pregnancy sickness does not appear to increase the risk to your baby. With severe pregnancy sickness or HG, there is an increased chance of having a baby with a lower-than-expected birth weight. If your symptoms are severe or continue later into pregnancy, your maternity team may offer additional ultrasound scans to monitor your baby's growth. This doesn't mean that your baby will be affected. It means your maternity team may want to keep a closer eye on things and make sure you're getting the support and treatment you need.

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The Emotional Impact Matters too

 

HG isn't just physically unpleasant. Being sick day after day can affect your mood, relationships, work, ability to care for other children and enjoyment of pregnancy. It can also be incredibly isolating. You might feel frustrated that everyone else seems to be enjoying their pregnancy while you're simply trying to get through the day. You might feel guilty about not being able to do your normal activities. You might even feel as though you're failing at pregnancy. You're not. You're unwell. If you're feeling persistently low, anxious, overwhelmed or unable to cope, tell your midwife, GP or maternity team. Emotional support is part of your care too. And if you're having thoughts of harming yourself or feel that you cannot keep yourself safe, seek urgent mental health support.

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Questions You Might Want to Ask

 

It can be difficult to think clearly when you're exhausted and nauseous, so you might want to save these somewhere handy.

• Do you think I have hyperemesis gravidarum?

• How dehydrated am I?

• Do I need blood or urine tests?

• What anti-sickness medicines could I try?

• How should I take them if I can't keep tablets down?

• Could I take more than one type of anti-sickness medication?

• Do I need fluids through a drip?

• Do I need thiamine?

• What would mean that I need to come back for further treatment?

• What support is available if this continues?

• Will my baby need additional growth scans?

• Who should I contact if my symptoms suddenly get worse?

• What support is available for my mental health?

 

You can also ask: "What are my options, and what are the pros and cons of each?"

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You don't need to accept a treatment without understanding what it is for and why it has been recommended.

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A Few Things to Remember

 

• Hyperemesis gravidarum is a severe form of pregnancy sickness.

• It can affect your physical health, mental wellbeing and everyday life.

• It isn't your fault.

• You don't have to simply endure severe symptoms because sickness is considered "normal" in pregnancy.

• Treatment is available, including anti-sickness medication and fluids when needed.

• Some people need hospital treatment, while others can be treated at home or through outpatient care.

• If you're struggling to eat or drink, losing weight or becoming dehydrated, seek help.

• Your emotional wellbeing matters too.

• Most pregnancy sickness improves with time, although HG can continue beyond 20 weeks and sometimes throughout pregnancy.

• You are allowed to ask for help, ask questions and ask for your symptoms to be taken seriously.

 

 

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