Hyperemesis gravidarum

Hyperemesis gravidarum (HG) is a
pregnancy condition characterised by
extreme levels of intractable nausea
and vomiting, fatigue, distorted
olfaction responses and hypersalivation.
Symptoms can lead to dehydration, malnutrition,
and secondary complications such as Wernicke’s
encephalopathy, oesophageal tears, hypocalcaemia and
thyroid dysfunction (Dean and Gadsby, 2013; MacGibbon
et al, 2015).
An estimated 30% of pregnant women suffer high
levels of morbidity from nausea and vomiting in
pregnancy (NVP) without receiving a diagnosis of HG
(Gadsby and Barnie-Adshead, 2011a). Symptoms of NVP
appear on a spectrum ranging from normal to severe,
and HG is considered to be at the extreme end of that
spectrum, affecting 1-1.5% of the pregnant population
(Einarson et al, 2013), and accounting for approximately
25 000 hospital admissions annually (Gadsby and Barnie-
Adshead, 2011b).
As yet, there is no internationally agreed