Hyperemesis gravidarum

What is hyperemesis gravidarum?

Hyperemesis gravidarum is a severe form of pregnancy sickness that causes persistent nausea and frequent vomiting. Unlike typical morning sickness, symptoms can be intense, long lasting and may make it difficult to keep food or fluids down, affecting daily life and wellbeing.

Because hyperemesis gravidarum varies from person to person, management often requires a personalised approach. Alongside medical assessment, factors such as rest, stress reduction and dietary support can play a role, but symptoms are often too severe to manage without specialist care, medication and close monitoring to reduce the risk of dehydration and other complications.

We provide expert assessment and treatment for hyperemesis gravidarum as part of our private maternity services at the Westminster Maternity Suite, based at St Thomas’ Hospital. Our experienced maternity specialists offer timely diagnosis, tailored treatment plans and compassionate, consultant‑led care to support you and your baby throughout pregnancy.

Hyperemesis gravidarum symptoms

Hyperemesis gravidarum is much worse than regular sickness or nausea during pregnancy. Typical sickness in pregnancy tends to occur only in the mornings and usually improves after the first trimester.

However, in hyperemesis gravidarum, sickness and vomiting may last considerably longer. In some women, it might not clear up completely until their baby is born.

Some of the signs that your pregnancy sickness could be hyperemesis gravidarum are:

• dark yellow urine
• dizziness and light-headedness
• fatigue
• feeling thirstier than usual
• prolonged, severe nausea and vomiting
• weight loss

If you are experiencing severe nausea and vomiting during pregnancy, specialist support can help reduce the risk of dehydration or weight loss.
Complete our enquiry form to book an appointment with one of our experienced obstetricians.

What causes hyperemesis gravidarum?

No one knows the exact cause of hyperemesis gravidarum. However, hormonal changes may be responsible. During your pregnancy’s first trimester, often when hyperemesis gravidarum peaks, the levels of a hormone called human chorionic gonadotropin increase.

Similarly, your oestrogen levels also increase during early pregnancy. Both of these hormone level increases may cause some women to experience more severe nausea and vomiting that either do not respond to at-home management or last longer than typical.

Complications of hyperemesis gravidarum

Hyperemesis gravidarum can make you feel very unwell, but it’s unlikely to cause complications with your pregnancy or harm your baby. However, if you lose considerable weight, there is a risk your baby will have a lower birth weight.

Hyperemesis gravidarum may also affect your emotional wellbeing. These extreme symptoms can be challenging to deal with and may lead to low mood and anxiety. If you’re dealing with the emotional aspect of hyperemesis gravidarum, remember you’re not alone and our caring team can help you through it.

If sickness in pregnancy is affecting your physical or emotional wellbeing, our specialist team can support you. Contact our team to discuss your care options with our team.

Diagnosing hyperemesis gravidarum

No single test can definitively diagnose hyperemesis gravidarum. Instead, one of our team of specialists will ask you about your symptoms and perform a physical examination to make sure that you and your baby are both healthy.

Sometimes, your obstetrician may need to carry out further antenatal testing to rule out any other conditions causing your symptoms.

Hyperemesis gravidarum treatment

Treating hyperemesis gravidarum can take trial and error, as some treatments that work for others might not work for you.

Getting enough rest and minimising stress can help support your wellbeing when managing your condition. Food also plays a vital role. Your body still needs nutrition even when you feel nauseous or are vomiting. Try eating carbohydrate and protein-rich meals and avoid foods high in fat. Lighter snacks may also be easier to keep down.

If specific foods trigger your hyperemesis gravidarum, avoid them as much as possible. Ginger is often recommended for nausea and sickness. However, with hyperemesis gravidarum, the effects of your condition may be too strong for home remedies and may require medical intervention instead.

Medical treatment for hyperemesis gravidarum

Our maternity specialists can prescribe you medication to help manage severe nausea and reduce the frequency of vomiting associated with sickness in pregnancy. This may include anti-sickness medication, steroids or a carefully monitored combination of treatments. As symptoms and responses vary, it can take time to find the best approach for you, with treatment adjusted as needed under specialist care.

In some cases, symptoms may not improve with medication alone. If nausea and vomiting become severe or persistent, hospital treatment may be required to prevent dehydration. This can include intravenous (IV) fluids to restore hydration and stronger anti-sickness medication given directly into a vein or muscle to help stabilise your symptoms.

Expert care for hyperemesis gravidarum

At Guy’s and St Thomas’ Specialist Care, our experienced maternity team provides personalised treatment for hyperemesis gravidarum, focused on your individual symptoms, medical needs and stage of pregnancy. Working closely with you, we aim to manage symptoms effectively while supporting your health and wellbeing throughout pregnancy.

Speak to our maternity specialists by completing our online enquiry form to access expert assessment and treatment for hyperemesis gravidarum as part of our private maternity services.