nuhahyearlyLaunch pricing - Get £50 off!nuhahyearlyHyperemesis gravidarum (HG) is a severe form of pregnancy sickness affecting about 1 to 3% of pregnancies. Unlike ordinary morning sickness it causes persistent vomiting, dehydration and weight loss, and usually needs medical treatment: anti-sickness medicines, IV fluids and sometimes a hospital stay. Seek help the same day if you cannot keep fluids down for 24 hours. HG counts as a pregnancy-related illness at work, and Pregnancy Sickness Support offers UK help.
Hyperemesis gravidarum (HG) is a severe form of pregnancy sickness that goes far beyond ordinary morning sickness. While most pregnant people feel some nausea in the first trimester, HG causes persistent, excessive vomiting that can lead to dehydration, weight loss, and being unable to carry on with everyday life. It is a recognised medical condition, not simply a bad case of morning sickness, and it responds well to the right treatment.
HG affects around 1 to 3% of pregnancies. It usually begins between weeks 4 and 7, tends to peak around weeks 9 to 13, and for most people eases by around week 20, though a minority have symptoms for longer. If this is you, please know that it is treatable and that you deserve support early.
The line between heavy morning sickness and HG is about how much it affects your body and your life:
Vomiting. Ordinary morning sickness comes and goes, and you can usually keep some food and fluid down. With HG the vomiting is frequent and relentless, sometimes many times a day, and keeping anything down can feel impossible.
Weight and hydration. Losing more than 5% of your pre-pregnancy weight, or becoming dehydrated (dark urine, passing little water, dizziness, a dry mouth), points towards HG rather than everyday sickness.
Daily life. HG is genuinely debilitating. Many people cannot work, look after other children, or get out of bed. Morning sickness, while unpleasant, does not usually stop life in this way.
Ketosis. When the body cannot get enough energy from food it breaks down fat and produces ketones, which show up on a urine dip. This is a sign your body needs extra support.
Contact your GP or maternity unit as soon as you think you have HG. Treating it early keeps it from getting worse, and you do not need to wait until things are severe. Seek help the same day if you cannot keep any fluids down for 24 hours, you are passing very little or very dark urine, you feel dizzy, faint or have a racing heart, you have lost weight, or you have tummy pain or a temperature. These are signs your body needs fluids and medical care rather than home measures.
UK care follows RCOG and NICE guidance and usually works step by step, and most people improve with the right combination.
Anti-sickness medicines. First-line options are antihistamine and phenothiazine antiemetics such as cyclizine, promethazine and prochlorperazine, which are well established in pregnancy. If these are not enough, second-line medicines such as metoclopramide, ondansetron or domperidone may be added. Guidance suggests adding medicines rather than simply swapping them, because they can work well together, so it is normal to end up on more than one.
Fluids. If you are dehydrated and cannot keep fluids down, you may be given intravenous (IV) fluids, either as a day case or through an ambulatory unit where you have fluids and go home the same day.
Hospital admission. Many people with HG need a hospital stay at some point for IV fluids, IV anti-sickness medicine and monitoring, and some need more than one admission across the pregnancy. This is common and nothing to feel discouraged by.
Vitamins and extras. Prolonged vomiting can lower thiamine (vitamin B1), so your team may top this up, and steroids are sometimes used for the most stubborn cases. If you are admitted, you may also be offered treatment to reduce the small risk of blood clots.
The emotional toll of HG is real and often underestimated. Weeks of relentless sickness can bring low mood, anxiety, isolation and grief for the pregnancy you had pictured. None of this is a weakness, and none of it is your fault. If you are struggling, tell your midwife or GP, because perinatal mental health support is available and you should not carry this alone. For a small number of people HG becomes so overwhelming that they begin to question whether they can continue. If you ever feel that way, please reach out to your care team straight away, as better treatment and specialist support may be within reach.
HG counts as a pregnancy-related illness, which matters at work. Any time off you need because of HG is pregnancy-related sickness absence and cannot lawfully be counted against you in attendance or disciplinary processes. Your GP or hospital can issue a fit note for time off, and your employer must still carry out a workplace risk assessment. If HG affects your job, our guide to UK maternity rights explains sick leave, pay and the protections you are entitled to.
Home measures are limited with HG, because it usually needs medical treatment, but a few things can help alongside your prescribed care. Sip small amounts of fluid often rather than large drinks; ice lollies and frozen fruit are sometimes easier than liquids. Eat whatever you can manage, whenever you can, without worrying about a balanced diet for now. Rest, because tiredness makes nausea worse. Keep a basin and supplies within reach, and accept every offer of help. You can also use our pregnancy symptom checker to see whether a symptom needs a call to your midwife.
This is the question every person with HG asks, and the reassuring answer is that in most cases babies do well, even when the mother feels dreadful. Your baby draws on your existing reserves, and the body is very good at protecting the pregnancy. Where HG is severe and untreated with a lot of weight loss, babies can be a little smaller, but treatment greatly reduces that. Getting help early and staying on top of fluids and medicine is the best thing you can do for you both.
Pregnancy Sickness Support (pregnancysicknesssupport.org.uk) is the UK's dedicated HG charity, with a helpline, peer support and resources for families and professionals. If you feel your symptoms are being dismissed, you have every right to ask for a second opinion or a referral to a specialist. HG deserves proper treatment, and help is available.
HG is a severe form of pregnancy sickness causing persistent vomiting, dehydration and weight loss. It affects about 1 to 3% of pregnancies and is far more serious than ordinary morning sickness, usually needing medical treatment.
Care follows RCOG and NICE guidance step by step. First-line anti-sickness medicines are antihistamines and phenothiazines such as cyclizine, promethazine and prochlorperazine; if needed, metoclopramide, ondansetron or domperidone are added. IV fluids treat dehydration, and many people need a hospital stay. Thiamine and, occasionally, steroids are also used.
Seek help the same day if you cannot keep any fluids down for 24 hours, you are passing very little or very dark urine, you feel dizzy or faint or have a racing heart, you have lost weight, or you have tummy pain or a temperature. Do not wait until you are severely dehydrated.
HG usually begins between weeks 4 and 7, peaks around weeks 9 to 13, and eases for most people by about week 20. A minority have symptoms for longer, sometimes to the end of pregnancy, but treatment helps throughout.
Yes. HG is a pregnancy-related illness, so your GP or hospital can issue a fit note, and this absence cannot be counted against you in attendance or disciplinary processes. See our UK maternity rights guide for the details.
In most cases babies do well even when the mother is very unwell, because the body prioritises the pregnancy. Severe untreated HG with significant weight loss can be linked to lower birth weight, so getting treatment early is important.
Home measures are limited, but sipping small amounts of fluid often, trying ice lollies or frozen fruit, eating whatever you can manage, and resting can help alongside prescribed treatment. Most people still need medical care as well.
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