Want to understand more about Hyperemesis Gravidarum or HG? HG is defined as a potentially life-threatening pregnancy disease that may cause weight loss, malnutrition, dehydration, and debility due to severe nausea and/or vomiting, and may cause long-term health issues for mother and baby(ies).

Incidence of Hyperemesis Gravidarum (HG)

Do you have morning sickness or Hyperemesis? Find out more about HG.

The criteria used to diagnose hyperemesis gravidarum (HG) often varies among health professionals and researchers. Very little research is done on the impact of hyperemesis as differentiated from morning sickness, thus the impact of HG is likely greatly underestimated. 

Women who are very severe are typically hospitalized, representing the 1-3% of pregnant women estimated as having HG. One study by Zhang, et al found a 10.8% incidence of severe vomiting, and another study found 16% of women using antiemetics.

There are hundreds, if not thousands, of additional women who terminate out of desperation when given inadequate treatment despite debilitating symptoms. Hyperemesis (HG) is not really a rare disorder. 

Impact of Hyperemesis Gravidarum (HG) 

Nausea and vomiting during pregnancy (NVP) can be mild (morning sickness) or more severe (hyperemesis gravidarum). NVP impacts every aspect of a woman's life. 

Research finds that the greater the severity and duration of symptoms, the greater the effect on the mother.

“A large majority (82.8%) reported that HG caused negative psychosocial changes, consisting of (1) socioeconomic changes, for example, job loss or difficulties, (2) attitude changes including fear regarding future pregnancies and (3) psychiatric sequelae, for example, feelings of depression and anxiety, which for some continued postpartum. Women who reported that their health-care provider was uncaring or unaware of the severity of their symptoms were nearly twice as likely to report these psychiatric sequelae.”

Risks of HG and Outcomes

Research shows that women with hyperemesis gravidarum (HG) have a higher risk of negative maternal and fetal outcomes. The greatest risk appears to be in women who have more weight loss, severe symptoms, and/or who fail to gain weight for two consecutive trimesters. The data varies partly due to the inconsistent criteria used to diagnose and define hyperemesis (HG) and determine severity levels.

Recent consensus by ICHG (International Collaboration for Hyperemesis Gravidarum) on a definition for HG will help bring uniformity to future research. 

Risks and Benefits of Medication for HG

One challenge with hyperemesis (HG) is weighing the risks of potential complications and misery with possible risks of anti-vomiting (antiemetic) therapies. Effective medications held until conservative measures fail delay needed treatment and may make vomiting more refractory.

There are a number of medications deemed safe with a long history of use. Yet, newer drugs often prove more effective, and do not significantly increase malformation rates

Although medication research is increasing (e.g. ondansetron) most studies find risks to be very small. Unfortunately, published abstracts sometimes makes the risk unclear. For example, one widely cited study finds a risk of cardiac defects, but the low rate doubled to less than 2%. Health professionals need to review the detailed data to determine the risks for their patients. 

The known adverse outcomes resulting from prenatal malnutrition often outweighs the small possible risks of medications. 

Potential Fetal Complications
of HG

Beyond the fetal loss rate of 34%,  children are at risk for numerous complications from hyperemesis gravidarum (HG), especially if the mother's symptoms are severe, prolonged, inadequately treated, or there is a delay in medical intervention. Specifically, weight loss over 15% of pre-pregnancy weight is highly predictive of adverse fetal impact. 

The exact causation is not entirely clear but high cortisol levels and stress, micronutrient deficiencies (vit K embryopathy, Wernicke’s encephalopathy), and inadequate maternal support, resources and access to care all play a role. Some problems may also be related to specific issues (e.g. IV infection, emboli, medication side-effects). Effective care is crucial.   

If women with HG are given early medical care enough to manage their symptoms and minimize nutritional deficiencies, both mother and child will be healthier now and in the future. 

The adverse health consequences for mother and child, as well as the costs of healthcare and lost productivity, affect families, the community, and the nation. These women and their children deserve excellent care and a chance at a healthy future.

Kimber MacGibbon, RN
HER Co-Founder/Director

Impact on Society

Hyperemesis Gravidarum is more than a pregnancy illness that impacts women and their families. HG impacts society. Conservative estimations suggest HG costs nearly $500 million annually just for inpatient hospitalization. There are also over 375,000 outpatient visits to emergency rooms for treatment of HG at an estimated cost of $2.5 billion, plus home health care, pharmaceuticals, outpatient infusion care, diagnostics, and frequent obstetrical visits. Considering so many women are treated outside the hospital to save costs, the actual cost is many times greater. The costs for HG treatment exceed $3 billion for HG each year in the US, and many women get inadequate care. The long-term effects of HG and its complications add many $1000's in costs over time.


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