Nausea and vomiting in pregnancy

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Nausea (the feeling of sickness) and vomiting is common in early pregnancy affecting around half of all pregnant women. It is often referred to as ‘morning sickness’ but can occur at any time of the day and may become constant. Most women do not require treatment however; persistent nausea and vomiting in pregnancy can lead to dehydration and weight loss and may require hospital treatment and occasionally admission.

What causes nausea and vomiting in pregnancy?

The exact cause of nausea and vomiting in pregnancy is unknown but it is likely to be due to the hormone changes. Symptoms normally begin between 4 and 7 weeks gestation and disappear by 16 weeks. It is more common in twin or multiple pregnancies where hormone changes are more pronounced.

Will it affect my baby?

In most cases the unborn baby is not affected as they get nourishment from your body’s reserves. Some studies have actually shown that having nausea and vomiting in early pregnancy is a good indication that the pregnancy is healthy.

What can I do to improve my symptoms?

Nausea and vomiting in pregnancy can be a difficult to cope with and may affect your mood, your work, your home situation and your ability to care for your family. However, you will need to develop coping strategies in order to prevent further dehydration and hospital admission. They may include the following:

• Eating small but frequent meals. Eat little and often of whatever you fancy. Dry foods that are high in carbohydrate are best, such as bread, crackers, etc. Eating a biscuit about 20 minutes before getting up is said by some women to help. If the smell of cooking triggers nausea aim to eat cold meals. Try to avoid spicy, fatty or fried foods.
• Ginger is said to help with nausea and vomiting such as ginger biscuits or ginger tea. You could also try ginger supplements but seek advice from you local pharmacist.
• Avoid triggers. Avoid situations that are likely to trigger sickness such as a smell or an emotional stress or warm / hot places.
• Drink plenty. Aim to drink at least two litres of water a day. Drink small amounts frequently as large amounts may cause vomiting. Avoid drinking fluids during meal times and immediately before or after a meal to avoid bloating.
• Rest. Make sure that you have plenty of rest and sleep in early pregnancy. Being tired is thought to make nausea and vomiting during pregnancy worse. You may need time off work and support from your friends and family. However, do make sure that you move around frequently to avoid you getting a deep vein thrombosis (DVT), a blood clot in within a vein.

What is Hyperemesis Gravidarum?

Hyperemesis Gravidarum is the medical term used for severe nausea and vomiting. This affects a small number of pregnant women and may require hospital admission. Due to the nausea you may not feel able to eat which can lead to a lack of vitamins in your system and signs of starvation. We test your urine for Ketones to help diagnose and monitor this. Ketones are produced if your body is forced to break down fat for energy if you are vomiting and are unable to keep food down.

What happens if I need investigations for Hyperemesis Gravidarum?

In severe cases of nausea and vomiting in pregnancy your GP may refer you for specialist advice from the gynaecology team where you will be seen in the Gynaecology Assessment Unit (GAU).

When you come into hospital we carry out a urine test and blood tests to check your blood count, urea, electrolytes and liver function for signs of dehydration. We will also arrange for an ultrasound scan to check the viability of the pregnancy.

What treatment is available for Hyperemesis Gravidarum?

If you require hospital treatment we will aim to resolve your symptoms using the acute (short stay) treatment pathway where you will be attached to a drip (intravenous infusion) and be given fluids that contain potassium, this is to replace the salts that you may lose through vomiting. Whilst it is generally best to avoid medications in pregnancy if your symptoms are severe you may require anti-sickness medication, which can be given intravenously in your arm, as an injection in your leg / bottom or in tablet form.

There is no evidence that suggests that this medication is harmful to the baby. We will also advice that you take Thiamine and Folic Acid which is a type of vitamin. If these medications become necessary they will be discussed fully with you.

The nursing staff will monitor and support you during your hospital stay. We use a scoring system called PUQE (pregnancyunique quantification of emesis and nausea) to assess the severity of your symptoms and will ask you questions such as how many times have you been or felt sick. Depending on your score you will be graded as mild, moderate or severe and we will re-visit this to see if there has been improvement and plan your discharge. We aim to improve your symptoms within 4 to 6 hours then you can be sent home with anti-sickness medication.

If your symptoms have not improved after this time you may require in-patient management for treatment of Hyperemesis Gravidarum. You will be admitted to the gynaecology ward and continue to have intravenous fluids.

In extreme cases we may also need to give you corticosteroids, called Hydrocortisone or Prednisolone, although this is quite rare. We will continue to assess you using the PUQE scoring system and aim to resolve your symptoms within 24 to 48 hours and discharge you home with anti-sickness medication and a follow up appointment with one of the gynaecology doctors in the gynaecology assessment unit.

References / useful links

BSUH NHS Trust (2016) Vomiting in pregnancy and hyperemesis gravidarum: Clinical Guidelines.
Royal College of Obstetricians and Gynaecologists. 2016.