Do I Have Morning Sickness or HG?
Women often ask if they have hyperemesis gravidarum (HG) or just a bad case of morning sickness. Early in pregnancy, it may be difficult to know because HG develops over time. If you find yourself losing weight rapidly (1-2 pounds [0.45-0.9 kgs.] a week or more) due to severe nausea and vomiting, you need to find a health professional who is familiar and comfortable caring for a woman with HG.
Sometimes a bad case of morning sickness will progress to HG due to ineffective or inadequate care. Delaying treatment is far too common to avoid any risks to the mother and child. However, many medications have been used for many years and the data shows little if any increase in risk to the unborn child, even if taken early in pregnancy. The risk of dehydration, ketone production, malnutrition, and rapid weight loss are likely greater than the risk of harming the unborn child with medications.
- Signs & Symptoms of a woman progressing into HG
- Laboratory Findings to look for in patient lab tests
- Risk Factors most common to women with HG
- Other Causes of NVP to Rule Out
The following chart illustrates the difference in severity between morning sickness and HG. Significant (>5% of your pre-pregnancy weight) weight loss and recurrent dehydration are classic signs of HG that most health professionals recognize.
| Morning Sickness | Hyperemesis Gravidarum |
| You lose little if any weight. |
You lose 5-20 pounds or more. (> 5% of prepregnancy
weight) |
| Nausea and vomiting do not interfere with your ability
to eat or drink enough each day. |
Nausea and vomiting cause you to eat very little and get
dehydrated from vomiting if not treated. |
| You vomit infrequently and the nausea is episodic but
not severe. It may cause discomfort and misery. |
You vomit often and may vomit bile or blood if not treated.
Nausea is usually moderate to severe and constant. |
| Dietary and/or lifestyle changes are enough to help you
feel better most of the time. |
You will probably require fluid hydration through a vein
and/or medications to stop the vomiting. |
| You typically will improve gradually after the first trimester,
but may be a little queasy at times during the remainder of your pregnancy. |
You usually feel somewhat better by mid-pregnancy, but
you may continue to be nauseous and/or vomit until late pregnancy. |
| You will be able to work most days and care for your family. | You will likely be unable to work for weeks or months, and may need help caring for yourself. |
Calculate Your Weightloss
Every woman with HG loses weight. Calculate the percentage you have lost to see if you should call your doctor.
Severity of Weight Loss*
| Time: | Significant Weight Loss (%): | Severe Weight Loss (%): |
| 1 week | 1-2% | > 2% |
| 1 month | 5% | > 5% |
| 3 months | 7.5% | > 7.5% |
| 6 months | 10% | > 10% |
Reprinted from Blackburn GL, Bistrian
BR, Maini BS, Schlamm HT, Smith MF. "Nutritional and metabolic assessment
of the hospitalized patient." JPEN. 1977; 1:11-22.
* Percent Weight Change = [(Usual Weight - Actual Weight) ÷ (Usual
Weight)] x 100
NOTE: This scale is based on non-pregnant subjects.
Updated on: Apr. 18, 2013
The Chronicles of Nausea
Beyond Morning Sickness