Written by Caroline Meyer

Nausea and morning sickness is quite common during pregnancy. In general it is quite harmless and by the time the pregnancy gets to 12 weeks, this have usually substantially decreased or gone away all together. For some women, the morning sickness can cause severe nausea and vomiting that can last all day during. This may also last a lot longer than normal morning sickness. This is known as hyperemesis gravidarum.

Hyperemesis gravidarum (HG) is quite different to morning sickness. Both conditions have side effects and complications, which are not the same as the other. To treat the symptoms correctly, it is important to distinguish between the two.

Morning sickness is often only a feeling of nausea which can be brought on by smells and tastes. This can also include vomiting. It typically starts during the first week of pregnancy but has disappeared by the 4th month. Where there is vomiting, it does not usually lead to dehydration. Women with morning sickness may also experience other symptoms such as loss of appetite and fatigue. They may also not feel up to accomplishing tasks they would usually carry out during the day. For some women, even brushing their teeth might bring on nausea and vomiting.

Hyperemesis gravidarum is a lot more serious and the nausea usually does not subside during the day. There may be severe vomiting which can lead to dehydration that could require treatment. The constant nausea and vomiting usually prevents the expectant mother from keeping fluids or food down. HG typically presents within the first 6 weeks of pregnancy but the nausea may not go away for the entire pregnancy. The mum to be will often feel exhausted and drained and may lose their appetite all together. They may also find it very difficult to perform the usual activities that they would normally. 

Hyperemesis gravidarum can lead to poor weight gain as well as dehydration. While there is no way to prevent HG or morning sickness, the symptoms can be adequately managed before it presents a major problem to the health of the mother or baby.


While almost all women will experience morning sickness to varying degrees during pregnancy, much fewer develop HG. Morning sickness and HG are not confined to the morning and nausea and vomiting can present throughout the day or night. HG and morning sickness are generally accepted as being caused by the human chorionic gonadotrophin hormone in the body. During pregnancy, this hormone is created by the placenta. In the early stages of pregnancy, this hormone spikes and a lot is produced as the placenta is being established.  The levels increase all throughout the pregnancy, but for some women, the body seems to adjust to these levels, while for others, it does not.


While there are no specific factors that determine if a woman will get hyperemesis gravidarum during pregnancy, but there does appear to be a heightened risk for women that have a family history of HG, are overweight, are pregnancy for the first time or who are carrying multiple babies at the same time. Abnormal cell growth inside the uterus, known as Trophoblastic disease can also cause hyperemesis gravidarum.


If you feel that your morning sickness is lasting longer or if you are experiencing dehydration, dizziness, lack of appetite, weight loss or more than mild discomfort from nausea and vomiting in the early stages of pregnancy, you should contact your health professional immediately.  They will more than likely do a standard physical exam, ask about your medical history as well as discuss the symptoms you are experiencing. The doctor will check for HG symptoms which can include a faster than normal pulse and low blood pressure. He may also check for dehydration by taking urine and blood samples. There may be additional tests done to ensure that the nausea and vomiting is not due to other gastrointestinal issues.

The doctor will possibly schedule an ultrasound scan to check for any internal issues and see if you may be carrying more than one baby. Depending on how severe the symptoms are, your doctor may look at simple nausea prevention through using ginger or vitamin B-6. They may also suggest that you eat bland foods, dry foods and eat small meats but a lot more frequently. Drink fluids to try and stay hydrated. In severe cases, you may be put on an IV to get fluid intravenously to rehydrate. 

Where the HG becomes severe enough to actually cause a threat the health of the baby or the mother, medication may be used. This will usually be anti-nausea drugs such as meclizine or promethazine. This will be administered via a suppository or IV to ensure it gets in to the system. Mediation during pregnancy can have a negative effect on the baby, but in severe cases of HG. Dehydration is considered a far greater risk. You doctor will discuss the potential health risks should you need medication for HG.

The good news is that HG will stop shortly after the hormones go back to normal after giving birth. 

Postpartum recovery can take a little longer for women with HG than normal. If you have any concerns, make sure to discuss them with your doctor or medical caregiver. Let your family know as you may need extra support during your pregnancy due to the symptoms you experience with severe morning sickness or HG.