Nausea and vomiting are very common in early pregnancy, affecting a large majority of women to some degree. For most, symptoms are mild and settle by around 16–20 weeks. But a small percentage develop hyperemesis gravidarum (HG): severe, persistent vomiting that causes dehydration, weight loss and electrolyte imbalance. HG can be debilitating and frightening, and women often report feeling dismissed. Nurses and midwives can make a real difference by recognising it and treating it promptly.
Hyperemesis gravidarum: key features
- Onset in the first trimester.
- Severe nausea and vomiting, unable to keep food or fluids down.
- Weight loss (often more than 5% of pre-pregnancy weight).
- Signs of dehydration: dry mouth, dark or reduced urine, tachycardia, dizziness.
- Ketones in urine and electrolyte abnormalities.
Rule out other causes
Vomiting that starts after about 10–11 weeks for the first time, or is accompanied by abdominal pain, fever, headache or other symptoms, needs investigation for other causes: urinary tract infection, gastroenteritis, malaria, hepatitis, pancreatitis, appendicitis, thyroid problems, and molar or multiple pregnancy (an early ultrasound is helpful).
Assessing severity: the PUQE score
The Pregnancy-Unique Quantification of Emesis (PUQE) score asks about the hours of nausea, number of vomits, and number of retches over 24 hours, giving a score from 3 to 15. Higher scores indicate more severe symptoms and help guide treatment and monitor response.
Nursing assessment
- Vital signs, weight, hydration status.
- Urinalysis for ketones and infection.
- Bloods as requested: electrolytes (low potassium, low sodium), kidney and liver function, full blood count, thyroid function.
- Ability to keep down food, fluids and medicines.
- Mental health: HG is associated with anxiety and depression, and some women consider ending wanted pregnancies because of it.
Treatment
- Antiemetics are safe and effective in pregnancy and should not be withheld. First-line options often include antihistamines (e.g. cyclizine, promethazine) or prochlorperazine; second-line options include metoclopramide (short-term, watch for movement side effects) and ondansetron (per current guidance); corticosteroids for severe refractory cases under specialist care.
- IV fluids: normal saline with potassium as needed. Avoid dextrose-only solutions initially because they can precipitate Wernicke’s encephalopathy in thiamine-deficient women.
- Thiamine (vitamin B1) supplementation for prolonged vomiting to prevent Wernicke’s encephalopathy (confusion, eye movement problems, unsteadiness).
- Ambulatory day-case care for rehydration is effective for many women and reduces admissions.
- VTE prophylaxis for admitted women: dehydration and immobility increase clot risk. See VTE prevention.
- Gradually reintroduce food: small, frequent, bland meals and fluids as tolerated.
Self-help for milder symptoms
- Rest; small, frequent meals; avoid triggers (smells, an empty stomach).
- Ginger may help mild symptoms.
- Sipping fluids little and often.
- Iron supplements can worsen nausea; temporarily pausing may be discussed with the clinician.
Believe her
Women with HG are sometimes told it’s “just morning sickness” or “all in your head”. HG is a recognised medical condition. Validate her experience, involve her partner and family, and arrange follow-up. HG often recurs in subsequent pregnancies, so a plan for next time helps.
Based on RCOG Green-top Guideline No. 69 (The management of nausea and vomiting of pregnancy and hyperemesis gravidarum) and NICE CKS. Educational content: follow local protocols.