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Dr. Chrysoula I. Liakou MD, PhD
- Treated online: Partly. A doctor can start, combine or change anti-sickness medicines; dehydration needs fluids and tests in person.
- What it is: severe nausea and vomiting that starts before 16 weeks, stops you eating and drinking normally, and strongly limits daily life.
- How common: about 1 to 3 in 100 pregnant women; Pregnancy Sickness Support estimates up to 30,000 pregnancies a year in the UK.
- How long: it often peaks at 9 to 13 weeks and can improve between 16 and 24 weeks; 1 in 5 with severe HG have it until the birth.
- Emergency: get urgent care if you cannot keep fluids down, pass very dark urine or none, or feel faint; call 112 if you collapse.
Do not book a video appointment if you cannot keep any fluids down, have not peed for 8 hours, feel faint or confused, vomit blood, or have severe tummy pain: you need to be seen in person urgently, and call 112 if you collapse.
Can an online doctor treat hyperemesis gravidarum?
Partly. While you can still keep some fluids down, a doctor by video can assess how severe the sickness is, start, combine or change anti-sickness medicines used in pregnancy, and follow you up. Hyperemesis gravidarum often needs care in person too: checks of your urine, weight and blood, fluids into a vein at a day unit, and sometimes a hospital stay. Not keeping fluids down, very dark urine, dizziness or weight loss means you need to be seen.
How an online consultation helps with hyperemesis gravidarum
- Severity assessed: How often you are sick, what stays down, your urine, weight and how you feel standing.
- Medicines started or changed: Anti-sickness medicines used in pregnancy, alone or together, without waiting weeks.
- In-person care when needed: Fluids and anti-sickness medicine into a vein at a day unit, before things get worse.
- Support: HG is exhausting and isolating; how you are coping is part of the care.
What the doctor checks in an online consultation for hyperemesis gravidarum
The doctor works out how dehydrated you are and whether the medicines are doing enough. The doctor asks about:
- Warning signs: no fluids kept down, no urine for 8 hours, feeling faint or confused, blood in the vomit, or tummy pain.
- The sickness: how many times a day you are sick, and what food and fluids stay down.
- Dehydration: thirst, a dry mouth, headaches, dizziness, and dark, strong-smelling urine.
- Weight: how much you have lost since the sickness began.
- Medicines: which anti-sickness medicines you have tried, for how long, and what happened.
- Your mood: how you are sleeping, coping at home and at work, and whether you feel low or anxious.
What is hyperemesis gravidarum?
Hyperemesis gravidarum (HG) is severe nausea and vomiting in pregnancy. It starts before 16 weeks, stops you eating and drinking normally, and strongly limits your daily life. It can cause dehydration and weight loss, and it often needs hospital treatment.
It is much worse than the usual nausea and vomiting of pregnancy: you may be sick many times a day and unable to keep food or drink down. It can start before a positive pregnancy test. See morning sickness for the milder, common form.
How common is hyperemesis gravidarum?
It affects about 1 to 3 in 100 pregnant women; the true figure is unknown, because some cases go unreported. Pregnancy Sickness Support estimates around 3% of pregnancies, up to 30,000 a year in the UK.
What causes hyperemesis gravidarum?
The exact cause is unknown. It is linked to the hormone changes of pregnancy, and research points to genetic differences linked to higher levels of a placental hormone called GDF-15. It can run in families, and it is more likely with twins or more.
Hyperemesis gravidarum or morning sickness?
Swipe sideways to compare →
| Morning sickness | Hyperemesis gravidarum | |
|---|---|---|
| Sickness | Feeling sick, sometimes being sick | Being sick many times a day |
| Eating and drinking | Possible, even if little | Food and drink do not stay down |
| Daily life | Hard, but you can carry on | Strongly limited |
| Dehydration and weight loss | Not usually | Common, and weight loss can be rapid |
| When it settles | Usually by 16 to 20 weeks | Often between 16 and 24 weeks; for some, not until the birth |
What are the symptoms of hyperemesis gravidarum?
Prolonged, severe nausea and vomiting, with signs of dehydration and weight loss.
The signs of dehydration are:
- feeling thirsty, with dry lips and a dry mouth
- tiredness and headaches
- feeling dizzy or light-headed, especially when you stand
- peeing less often
- dark yellow, strong-smelling urine
When does hyperemesis gravidarum start, and how long does it last?
It starts early, before 16 weeks, and often peaks at 9 to 13 weeks. Some symptoms can ease around 16 to 24 weeks, but about 1 in 5 women with severe HG have symptoms throughout the pregnancy.
How is hyperemesis gravidarum treated?
With anti-sickness medicines used in pregnancy, alone or together, fluids into a vein when you are dehydrated, and sometimes steroids. Changes to diet alone will not stop HG.
- With your doctor: anti-sickness medicine when the sickness does not settle or affects daily life.
- At a day unit: checks of your hydration and weight, urine and blood tests, and a scan if you have not had one; fluids and anti-sickness medicine into a vein. Many women then go home.
- In hospital, if needed: fluids into a vein until you can drink, anti-sickness medicine, thiamine (vitamin B1), medicine for stomach acid, compression stockings and heparin injections to lower the risk of blood clots.
Anti-sickness medicines
The RCOG order starts with doxylamine with pyridoxine, the only medicine licensed for pregnancy sickness in the UK, and cyclizine; then prochlorperazine, chlorpromazine or promethazine; and if these fail, metoclopramide, domperidone or ondansetron. Several may need to be tried, and occasionally two or more are combined.
Steroids
Corticosteroids are considered if HG continues despite fluids into a vein and regular anti-sickness medicine, or if you lose a lot of weight. Most women stop them by 18 to 20 weeks, and those taking them are offered a test for gestational diabetes.
Is the treatment safe for my baby?
All of these medicines are considered safe in pregnancy, although some are not licensed for it, and untreated HG may cause more harm than the medicines. HG is unlikely to harm the baby when it is treated well; weight loss raises the chance of a low birthweight, so extra scans may be offered.
What are the risks of hyperemesis gravidarum?
- dehydration and weight loss, which need fluids and closer monitoring
- a lower birthweight for the baby, when weight loss is significant
- blood clots, which are rare; preventive treatment is given if you are dehydrated and not moving much
- tears in the oesophagus, the tube from the mouth to the stomach, if HG is not treated
- low mood and depression, anxiety and isolation
Support, and how partners can help
HG can affect your mood, your work, your home life and your social life, and some women become depressed and need counselling. Talk to your midwife or doctor, your partner, family and friends. Pregnancy Sickness Support, a UK charity, runs a support network and can put you in touch with someone who has had HG.
How partners and family can help
Practical help matters most: meals, childcare, lifts to appointments and time to rest. Well-meant food tips will not fix HG, because diet changes alone do not relieve it. If your partner is getting worse, not drinking or not peeing, help them get seen.
Will I get hyperemesis gravidarum again?
It is likely to come back in a future pregnancy if you had it before.
Plan ahead: arrange childcare and time to rest, repeat what helped last time, and talk to a doctor about starting anti-sickness medicine early.
What might the doctor recommend for severe pregnancy sickness?
What happens next depends on what stays down and how dehydrated you are. This is the framework the doctors use:
Swipe sideways to compare →
| What you have | Likely first step | Suitable for online care? | When in-person care is needed |
|---|---|---|---|
| Collapse, or confusion | Emergency care | No | Call 112 now |
| No fluids kept down, or no urine for 8 hours | Fluids and anti-sickness medicine into a vein | No | Day unit or hospital urgently |
| Sick many times a day, some fluids staying down | Starting or combining anti-sickness medicines | Yes | If you cannot keep fluids down |
| Medicines tried without enough relief | Changing or adding a medicine | Yes, with follow-up | A day unit if weight loss or dehydration starts |
| Low mood with HG | Support, and a plan for help | Yes | If you have thoughts of harming yourself |
Severe sickness and the medicine not working yet? A doctor can review it with you in one consultation.
See available times →Special situations
Twins or more
A multiple pregnancy makes HG more likely, so get help early rather than waiting for it to pass.
Sickness that starts after 16 weeks
HG starts before 16 weeks. Vomiting that begins later, or comes with tummy pain or pain when peeing, points to another cause.
After you leave hospital
Symptoms can come back. If dehydration returns, contact your midwife, your doctor or the maternity unit again.
When hyperemesis gravidarum is treated online, and when you need in-person care
Treated online: assessing severity while some fluids stay down, starting, combining or changing anti-sickness medicines, follow-up, support, and planning for the next pregnancy.
In-person care: not keeping fluids down, no urine for 8 hours, weight loss, blood and urine tests, fluids into a vein, steroids, and admission.
When to get in-person care
Call 112 now for:
- collapsing, or fainting and not coming round
- confusion or extreme drowsiness
- vomiting large amounts of blood
Get medical advice the same day for:
- not keeping food or fluids down
- very dark urine, or not peeing for 8 hours or more
- feeling dizzy or faint when you stand up
- losing weight, or tummy pain
- symptoms coming back after a hospital stay
How Mobi Doctor works
- Book a time that suits you: daily 7am–11pm CEST. You can see a doctor over video, usually within 15 minutes. No subscription, and the exact price is shown before you pay.
- Speak to a licensed doctor about the sickness: say how often you are sick, what stays down, how much weight you have lost, and which medicines you have tried.
- Leave with a plan: the medicine to start or change, the signs that mean fluids in person, and when to follow up. If the doctor prescribes, use the prescription at a pharmacy near you.
No sign-up needed
Not sure it’s hyperemesis gravidarum? Tick every symptom you have to see each page that mentions it. It finds the right page, not a diagnosis: a doctor gives you that on a video call. If you have an emergency sign listed on this page, call 112 instead.
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Similar symptoms, different condition? Morning Sickness can start the same way. Compare them, or look up any other symptom in the full symptom checker.
Frequently asked questions about hyperemesis gravidarum
What is hyperemesis gravidarum?
Hyperemesis gravidarum is severe nausea and vomiting in pregnancy that starts before 16 weeks, stops you eating and drinking normally and strongly limits your daily life, often with dehydration and weight loss. It is much worse than ordinary morning sickness, it affects about 1 to 3 in 100 pregnant women, and it often needs anti-sickness medicines and sometimes fluids in hospital.
How is it different from morning sickness?
Morning sickness, unlike hyperemesis gravidarum, lets you eat and drink, even if little, and usually settles by 16 to 20 weeks. HG means being sick many times a day, with dehydration and weight loss.
How common is hyperemesis gravidarum?
Hyperemesis gravidarum affects about 1 to 3 in 100 pregnant women, up to 30,000 pregnancies a year in the UK, and it is the most common reason for admission to hospital in early pregnancy. Ordinary nausea and vomiting affect about 7 in 10 pregnancies, so the difference is severity: HG means being sick many times a day, losing weight and becoming dehydrated.
When does hyperemesis gravidarum start?
Hyperemesis gravidarum starts early, before 16 weeks and usually in the first 6 to 8 weeks, sometimes even before a positive pregnancy test; it often peaks at 9 to 13 weeks. Severe sickness that begins after 16 weeks is not HG and needs a doctor to look for another cause, such as a stomach bug, a urine infection or gallbladder trouble.
Does hyperemesis gravidarum go away?
Hyperemesis gravidarum can improve between 16 and 24 weeks, when hormone levels change, and many women are much better by the middle of pregnancy, but about 1 in 5 women with severe HG have symptoms until the birth, after which it stops within days. Treatment makes the months in between bearable, and starting medicine early in the next pregnancy often keeps it milder.
What causes hyperemesis gravidarum?
The exact cause of hyperemesis gravidarum is unknown. It is linked to pregnancy hormones and to genetic differences in the placental hormone GDF-15, and it can run in families.
What is the best treatment for hyperemesis gravidarum?
There is no single best treatment for hyperemesis gravidarum: anti-sickness medicines used in pregnancy, such as cyclizine, prochlorperazine, metoclopramide or ondansetron, alone or in combination, are the mainstay, with fluids and vitamins into a vein when you are dehydrated, and steroids for the most severe cases. Ginger, acupressure bands and small frequent meals help some women but are not enough on their own for HG.
What can I do at home with hyperemesis gravidarum?
Sip fluids little and often, ice lollies, flat lemonade or oral rehydration drinks, rather than large glasses; eat whatever stays down, in small amounts every hour or two, take the anti-sickness medicine on time, before the nausea builds; rest, and accept help with everything else; and avoid smells, screens and motion that set you off. Keep a note of how much you drink and how often you pee, because that tells a doctor when hyperemesis gravidarum needs fluids in hospital.
When should I go to hospital with hyperemesis gravidarum?
Go to hospital, or contact your maternity unit, if hyperemesis gravidarum means you cannot keep fluids down for 24 hours, have not peed for 8 hours or your urine is very dark, feel dizzy or faint when you stand, are losing weight, vomit blood, have tummy pain or a high temperature, or feel confused. These are signs of dehydration or of another problem, and they are treated with fluids into a vein and tests.
Does hyperemesis gravidarum harm the baby?
Hyperemesis gravidarum is unlikely to harm the baby when treated well. Weight loss raises the chance of a low birthweight, so extra scans may be offered.
Will I get hyperemesis gravidarum again?
Hyperemesis gravidarum is likely to come back: most women who have had it get it in a later pregnancy, though it can be milder or more severe. Plan ahead: talk to a doctor before trying again, keep a record of what helped, arrange support at home for the early weeks, and ask about starting anti-sickness medicine as soon as pregnancy is confirmed, since treating early tends to keep it under control.
Can hyperemesis gravidarum be prevented?
Hyperemesis gravidarum cannot be prevented, because it comes from pregnancy hormones and genes, but it can be made milder: women who have had it before are advised to start anti-sickness medicine as soon as pregnancy is confirmed, before the sickness takes hold, to take a multivitamin from before conception, and to line up practical support early. Treating the first signs promptly, rather than waiting to see, lowers the chance of dehydration and hospital admission.
Can an online doctor treat hyperemesis gravidarum?
Partly. A doctor can assess hyperemesis gravidarum by video, check you for the signs of dehydration, start, combine or change anti-sickness medicines that are used in pregnancy, and plan how to keep fluids and food down, as long as some fluids are staying down. Dehydration, weight loss that continues, or being unable to keep anything down need fluids into a vein and blood tests in person.
- Severe vomiting in pregnancy (hyperemesis gravidarum), NHS, National Health Service (UK), reviewed 11 January 2023.
- Pregnancy sickness (nausea and vomiting of pregnancy and hyperemesis gravidarum), RCOG, Royal College of Obstetricians and Gynaecologists, May 2024.
- What is hyperemesis gravidarum?, Pregnancy Sickness Support, UK charity, accessed 15 October 2026.
- Vomiting and morning sickness, NHS, National Health Service (UK), reviewed 17 April 2024.
This page is for information only and is not a substitute for a medical consultation. Guideline links are provided for transparency; treatment decisions are made with your doctor.
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