Hyperemesis: When to Go to Hospital in the UK
This complete UK guide explains what you need to know, when to seek help, and how to access the right care. Written by Nub Hub UK for expectant parents navigating pregnancy.
When should you go to hospital with hyperemesis?
Hyperemesis gravidarum can become a medical emergency if dehydration and weight loss are not addressed. Knowing when to seek urgent hospital care is essential for your safety and your baby wellbeing. In the UK, you can attend your local maternity assessment unit, walk-in centre, or A and E depending on severity and time of day. Never hesitate to seek help if you are uncertain. Hospital teams regularly treat HG and will not dismiss your symptoms.
Red flag symptoms requiring urgent care
Go to hospital immediately if you have not kept any fluids down for twenty-four hours, are vomiting blood or material that looks like coffee grounds, have dark or absent urine, feel dizzy or faint when standing, experience confusion or rapid heartbeat, have severe abdominal pain, or cannot stand without support. These signs indicate significant dehydration or complications that require intravenous fluids and medical assessment without delay.
Ketones and what they mean
When your body cannot get energy from food, it breaks down fat, producing ketones. Moderate to high ketones in your urine are a sign your body is under nutritional stress and a common reason for hospital admission with HG. Your midwife or GP can test your urine for ketones at a routine appointment. If ketones are high, you will likely be referred for intravenous fluids to rehydrate and restore your electrolyte balance.
Weight loss thresholds
Losing five percent or more of your pre-pregnancy body weight is a diagnostic marker for HG and a strong indication for hospital assessment. If you are losing weight rapidly, unable to eat, or your clothes are becoming loose within a week, contact your GP or midwife the same day. They can weigh you, assess hydration, and decide whether admission is needed. Persistent weight loss risks nutritional deficiency for both you and your baby.
What happens at hospital?
On arrival, staff will check your vital signs, test your urine for ketones, and take blood to assess dehydration, kidney function, and electrolyte levels. You will be given intravenous fluids, usually a saline drip, and anti-sickness medication by injection if oral tablets are not staying down. Most women feel significantly better after a few hours of fluids. Some need a short admission of one to three days to stabilise and restart oral intake.
After discharge and repeat visits
Going home does not mean the episode is over. HG can recur, and some women need multiple admissions. Ask for a clear plan with your GP and midwife, including which medications to take at home, warning signs to watch for, and when to return. Keep a symptom diary noting fluid intake, vomiting frequency, and weight. Pregnancy Sickness Support has useful templates. Multiple admissions are common in HG and not a sign of failure. You are managing a serious condition.
Key takeaways
- When should you go to hospital with hyperemesis?: covered above with practical, UK-specific guidance.
- Red flag symptoms requiring urgent care: covered above with practical, UK-specific guidance.
- Ketones and what they mean: covered above with practical, UK-specific guidance.
Nub Hub UK provides evidence-based pregnancy information for UK families. Always consult your healthcare team for personalised advice.