Nausea and vomiting are very common early symptoms of pregnancy, affecting approximately two thirds of Australian mothers during the first 6-20 weeks of pregnancy. Although symptoms can occur at any time of day, many women report that their nausea is at its worst during the mornings which is why it is commonly referred to as 'morning sickness'. 

It’s thought that the large surges of hormones, changes in carbohydrate metabolism and reduced blood pressure may be responsible for pregnancy nausea and vomiting. Morning sickness can be challenging but for the most part, it is intermittent in nature and still allows the pregnant mother to continue with her daily activities such as work, care giving, eating and drinking. It is also uncommon for morning sickness to extend into the later half of the second trimester or third trimester, but it certainly is possible.

By contrast, hyperemesis gravidarum is a debilitating pregnancy condition which is categorised by persistent nausea and vomiting throughout the day, often for the duration of pregnancy. Considered quite rare, hyperemesis gravidarum affects approximately 1% of pregnant mothers, with serious health consequences for both the mother and baby. The relentless nature of hyperemesis gravidarum makes it challenging for the mother to keep food or water down long enough to absorb.

This means the risks and physical complications of hyperemesis gravidarum include:

  • Severe dehydration
  • Electrolyte imbalance
  • Foetal nutrient deficiency
  • Weight loss. 

Of course, this takes an incredible toll on energy levels, ability to carry out regular daily tasks and mental health. Many women with hyperemesis gravidarum, also report symptoms of depression and anxiety as they struggle to get enough rest, water, and food.

Symptom Morning Sickness Hyperemesis gravidarum

Weight loss
Not a common symptom with typical morning sickness Can be quite common in hyperemesis gravidarum due to persistent vomiting and inability to keep any food down.
Nausea Usually intermittently present with most people finding it manageable. Consistent nausea alongside vomiting is common in and can last for the duration of pregnancy.
Vomiting Although vomiting may occur occasionally, it doesn’t impact daily function including work, care giving, sleep, eating or drinking. Debilitating frequency of vomiting which impairs basic daily function, including sleep, eating and drinking.
Dehydration Not typical or likely with intermittent symptoms of nausea and vomiting. Severe dehydration and electrolyte imbalance possible due to inability to retain fluids.



We recommend speaking with your GP if you are concerned that you may have hyperemesis gravidarum to discuss possible treatment plans.

To learn more about EmeTerm wristband for safe, effective and drug-free morning sickness relief, click here. 



Hyperemesis gravidarum - Maternal, child and family health (nsw.gov.au)

Severe vomiting in pregnancy - NHS (www.nhs.uk)

Pregnancy - morning sickness - Better Health Channel