Below is a list of frequently asked questions for mothers:

The exact causes of HG are becoming more understood as genetic studies are providing some answers. We know that hormonal changes, dehydration, nutritional deficiencies, and the overall stress on the body’s chemistry and functioning contribute to nausea and vomiting in pregnancy.

The cause is likely due to several factors that may differ for each woman, including hormonal sensitivity and genetics. It is not a woman’s fault, and women cannot control whether or not they vomit or are nauseous when pregnant.

Vomiting is often stimulated by a place in the brain known as the vomiting center. It may also be stimulated by changes in the stomach and intestines that are caused by pregnancy hormones. Emotional distress may worsen vomiting and results from the misery and debility, but is not the cause.

Some known risk factors that worsen nausea/vomiting or often exist pre-pregnancy include:

  • Altered sense of taste
  • Sensitivity of the brain to motion
  • Food leaving the stomach slowly
  • Increased sense of smell
  • Insufficient fluids or nutrition
  • Rapidly changing hormone levels
  • Gastric reflux
  • Physical and emotional stress
  • Vitamin deficiencies
  • Exertion & fatigue
  • Excess saliva (ptyalism)

Studies vary, but most find that women have a good chance of experiencing HG again in future pregnancies. Some health conditions are more common in those who have HG. Statistics suggest over 70% of women will have it with each pregnancy and those with more than one experience of HG have a greater risk of re-experiencing HG. It also seems to occur in similar patterns and severity, or worsen each time, though it is not always consistent. Those who have mothers, grandmothers, or sisters who have had HG will often have at least some nausea and vomiting during pregnancy.

More Info on Risk Factors

In most women, symptoms will begin within 4-6 weeks after conception. The nausea/vomiting will generally ease after the first trimester and resolves by 20 weeks in about half of women. However, about 10-20% of mothers will find nausea and vomiting last until delivery, though it is usually less severe. If you have had HG in previous pregnancies, it will often follow a similar pattern of duration and severity.

Due to the risk of stating a medication is safe for use during pregnancy, few if any drug manufacturers will say their drugs are intended for use during pregnancy or for a pregnancy condition such as HG. However, due to the misery and debility women with HG face, physicians will often treat HG with medications deemed generally safe due to their history of being used for pregnancy nausea and vomiting for decades (e.g. Phenergan, Unisom).

It is unfortunate that many health professionals will only consider older medications, as they are often found to be much less effective than newer medications (e.g. Zofran, Kytril), especially in those with more severe HG. Newer medications are not necessarily unsafe, they just don't have studies to demonstrate their safety. The risk of treating with effective medications is often less risky than not treating HG or waiting until a mother is very ill. Chronic dehydration and malnutrition worsen symptoms and can adversely affect the baby.

Above all, know that effectively treating symptoms early in pregnancy can reduce symptom severity and decrease the time it takes to recover. Delaying treatment until a woman has been vomiting for several weeks makes it harder to gain control over the vomiting cycle. Women have the right to adequate healthcare.

Consult with another health professional if needed to get better care. A partner or a significant other may need to advocate for mothers who are very sick. Women who lose more than 8-10% of their pre-pregnancy weight and have a doctor unwilling to prescribe effective medications or other treatments may want to seek a second opinion from a high-risk obstetrician or maternal-fetal medicine specialist.

Our Referral Network lists health professionals other women with HG have recommended or those who have requested to be added. We don’t personally interview or guarantee their expertise. You will also find information on how to find a practitioner experienced in treating HG if one is not listed in your area. Email us at for immediate assistance with finding referrals and volunteer support.

More Info on Treatment Options

First of all, understand that no one except those who have had HG will truly understand how it feels to suffer from HG. Sometimes, it is helpful to explain that HG is like having food poisoning for weeks (or months). Most people know how miserable and exhausting just a day or two of that is.

Also, keep in mind that isolation, while often necessary to minimize triggers of nausea/vomiting, increases depression and/or anxiety, especially if HG lasts beyond mid-pregnancy or is very severe. Emotional distress and trauma are common due to the misery, fear, and debility of HG. If you feel you are depressed, talk to your doctor about medication or try natural homeopathic remedies. Some prescription medications may be available after the first trimester.

  • Support Groups: Find others who have had HG for support. It’s helpful to know you are not alone.
  • Survival Tips & Brochures: Print out or refer others to our information on how they can help. Remember, only those who experience HG will completely understand.

Vomiting more than a few times a day and losing weight are the hallmarks of HG. Being unable to keep enough water down to stay hydrated, vomiting bile or blood, and losing more than 1-2 pounds (0.45-0.9 kg) in a week, is likely HG.

Women may have great difficulty taking care of normal responsibilities and/or going to work for weeks or even months. If HG is severe, a woman may have trouble just caring for herself, such as showering and preparing food. This is not something she can control, especially without adequate treatment. Immediate medical intervention is critical if HG is moderate to severe.

Hyperemesis GravidarumMorning Sickness
You lose 5-20 pounds or more. (> 5% of prepregnancy weight).You lose little if any weight.
Nausea and vomiting cause you to eat very little and get dehydrated if not treated.Nausea and vomiting rarely interfere with your ability to eat or drink enough each day.
You vomit, or feel the need to, often and may vomit bile or blood if not treated. Nausea is usually moderate to severe and constant.You vomit infrequently and the nausea is episodic but not severe. You have significant discomfort and misery.
You will probably require fluid hydration through an IV and/or medications to ease your symptoms.Traditional remedies like diet or lifestyle changes are enough to help you feel better most of the time.
You usually feel some relief by mid-pregnancy, but may be nauseous and/or vomit until late pregnancy.You typically improve after the first trimester, but may be queasy at times throughout pregnancy.
You will likely be unable to work for weeks or months, and may need help just caring for yourself.You will be able to work most days and care for your family, though less than usual at times.
You may feel anxious about what lies ahead if you had HG before. You will likely become depressed due to misery and physical depletion. More severe HG often is traumatic and may impact you for years to come.You may feel a bit depressed at times, especially if you have more severe nausea, but are able to be your usual self most of the time. You will likely forget most of the unpleasantness after delivery.

If she cannot keep more than a few bites of food or a few sips of water down for 24 hours or more, or loses 2 or more pounds (0.9 kg) in one week, vomits blood, faints, or generally feels very unwell, call the doctor. If she has several of these symptoms and it is after working hours, it may be necessary to go to the ER or an urgent care center.

You can buy Ketostix at a local pharmacy without a prescription. These test for starvation or lack of carbohydrates but are not reliable to diagnose HG. They are simply an indicator that a woman needs more calories.

If someone has ketones in their urine (the test is positive), fluids with vitamins are usually needed through an intravenous (IV) line at the doctor's office, ER, hospital, or an urgent care center. Additional nutritional therapy may also be needed if ketones recur. Ketones may be harmful to the baby if not treated.

After vomiting for 2-3 weeks and eating very little, women need IV vitamins including a multivitamin (MVI), and B complex (or at least thiamin). Sometimes this is forgotten, so make sure you ask about it, it is very important. B vitamins are most critical as they are depleted rapidly, especially in the presence of a high carbohydrate (e.g. sugar) diet, and come from foods not often craved during pregnancy. Remember, dehydration, vitamin deficiencies (esp. thiamin/B1) and ketones worsen nausea and vomiting and need to be monitored closely when mothers are very ill.

Call a health professional if any of the following occur:

  • Abdominal pain, bleeding, or cramping
  • Difficulty thinking or focusing
  • Difficulty walking or talking
  • Extreme fatigue and very low energy
  • Little if any food or fluids stay down for 24+ hours
  • Little saliva and a dry mouth
  • Moderate or severe headache and/or fever
  • Muscular weakness or severe cramping
  • Repeated vomiting or retching daily
  • Severe nausea prevents eating for 2+ days
  • Shortness of breath or dizziness
  • Urination is infrequent (≤ 3 times/day) and minimal amount
  • Urine is dark yellow and concentrated
  • Visual disturbances, or fainting
  • Vomit is bright red with blood (or looks like coffee grounds)
  • Loss of 2 pounds (0.9 kg) or more in a week

Since the exact cause is not known and is likely due to more than one factor, it is not preventable. However, the symptoms are often more manageable and less severe if adequate treatment is given early in pregnancy. Sometimes HG is less severe if you plan ahead and prepare for pregnancy. This includes eating very healthy, taking antioxidants and prenatal vitamins for several months, and making sure you are in the best health possible.

Underlying conditions such as gall bladder disease can worsen HG. Finding a health professional experienced in treating HG and who knows your history is crucial. Make a plan based on what worked for your last pregnancy and find a health professional willing to help you get the care you need.

Preparing for HG

In most cases, women who lose weight during their first trimester have normal babies. Adequate nutrition is important for the baby, but his/her requirements are very minimal during the first few months. Your body should have sufficient stores for the baby during this time. High-quality vitamins can be helpful for most women, but those with HG often cannot tolerate them, especially if they contain iron. Studies show certain vitamins (e.g. folic acid) are critical during the few months prior to pregnancy and up to about 6 weeks gestation. This is when the risk of miscarriage is great and the spine is forming. Antioxidants may prevent miscarriage according to some studies.

Since HG often does not make vitamins intolerable until around 6 weeks, just do your best to take them as long as you can. You can try gummies, creams, patches, and sublingual (under the tongue) forms of vitamins (especially B1 & B6, and folic acid) that can be ordered online or found at some health food stores. Taking a single vitamin instead of a combination may be better tolerated. (e.g. B6 versus B complex) If you are admitted for IV fluids, make sure a multivitamin and B complex are added to your fluids, especially if you have been vomiting frequently for more than 2 weeks. This is not routinely done, unfortunately.

The risk to the baby is greatest if the mother is dehydrated for extended periods of time, loses 10% or more of her pre-pregnancy weight, and does not receive vitamins or other nutritional support, or fails to gain weight for 2 consecutive trimesters. Obviously, if the mother develops other complications, they also present an increased risk. Most studies, however, show that women with hyperemesis have normal babies unless they are severely ill and receive inadequate treatment.

There is always a risk with any medication taken during pregnancy. However, medications most often prescribed typically present less risk to the mother and child than chronic dehydration and malnutrition. The risk decreases after the first trimester or around 9 weeks, but if vomiting is left uncontrolled until then, the stress on the body is great and it is much more difficult to stop the vomiting. These women are then at greater risk for complications and a prolonged recovery. They often will have great difficulty caring for themselves and their family for months.

Medications are often more effective if started early when she is hydrated, less nutritionally deficient and in better overall health. This proactive approach also may prevent more severe symptoms. It can be compared to pain control. Most health professionals know that when pain medicine is given early, rather than later, the pain is easier to control. The same holds true with vomiting. The consequences and complications are typically less if the nausea and vomiting are controlled earlier than later.

Do not be alarmed if the medication insert says something such as "Not for use during pregnancy." This is commonly written to minimize liability for pharmaceutical companies. Discuss any concerns with your physician.

More Info on Medications