Nausea in pregnancy: What might help to reduce the symptoms of “morning sickness”?

For some women who experience nausea and vomiting in pregnancy it might be worth trying ginger or acupressure, even if it is not absolutely clear whether these measures are helpful. If the nausea is only mild, it is good for you to pay attention to your body’s signals and then, for instance, avoid the foods that make you more nauseous.

Nausea and vomiting are very common in early pregnancy: at least half of all women are affected by some nausea in the first few months of pregnancy. Although it is called morning sickness, and it can actually be worse in the mornings, it may last all through the day too. It is not known why pregnancy is so often accompanied by these symptoms. One theory is that it is related to a hormone produced in pregnancy. It is usually not a sign of illness or a problem for the baby.

Morning sickness is typically gone by the end of 16 weeks of pregnancy. But it sometimes continues later into pregnancy – in about 1 or 2 out of every 10 pregnant women. It is not only a problem because it makes pregnant women feel so unwell – it can also be more difficult to eat a healthy diet or to stay well-nourished if you are nauseous and vomiting.

Most women try to manage their nausea without using drugs. The most common advice is to eat carbohydrates, such as toast, biscuits or bananas. Eating smaller meals more frequently throughout the day is another strategy. There is no good research testing different diets for their ability to relieve nausea and vomiting in early pregnancy.

Many pregnant women also try alternative approaches, including homeopathic medicine or herbal products made from chamomile, peppermint, or raspberry leaves. These have not been scientifically tested either.

Research on treatments for nausea in pregnancy

To find out which medications and non-drug strategies help to reduce nausea and vomiting in early pregnancy, researchers from the Cochrane Collaboration looked for randomized controlled trials. This kind of trial is the most reliable way to find out whether a treatment works. People are randomly divided into groups. The people in one of the groups receive the treatment that is being tested, and those in comparison groups have a different treatment, a placebo (dummy treatment) or no treatment. Because the participants are randomly assigned to the different groups, the groups are as similar as possible and the results can be compared later. If people in one of the groups are feeling a lot better by the end of the trial, the researchers can be quite sure that this difference is because of the treatment they had. You can read more about why this kind of trial is important here.

The researchers found trials involving the following treatments: acupuncture, acupressure, several medications and, in particular, ginger supplements. Trials involving pregnant women who had an extreme form of nausea and vomiting called hyperemesis gravidarum were not included.

Overall, there were only a few trials on the effects of vitamin B6 and various medications in the treatment of morning sickness. This means that it is not possible to draw any conclusions about the effects of medications. In some cases there was not enough information on possible adverse effects. But the medications tested are not believed to harm the developing baby.

Research on alternative treatments

Two randomized controlled trials involving a total of 648 pregnant women looked at whether acupuncture can effectively relieve nausea and vomiting. In these trials, one group of women had acupuncture and another group had fake acupuncture. The results suggest that acupuncture does not help to relieve nausea and vomiting.

Acupressure is a variation of acupuncture which involves applying pressure to specific points on the body. For the treatment of nausea, it is common to either apply pressure to a particular point on the wrist (the so-called P6 acupressure point) using a special wristband, or stimulate particular points on the ear (auricular acupressure). The trials here had very mixed results.

Trying out ginger

Researchers from the Cochrane Collaboration also looked into whether ginger can relieve nausea and vomiting in pregnancy. They analyzed four trials involving 283 pregnant women. In these trials, one group of women took ginger, and another group either took a placebo or vitamin B6. The trials most often tested the effect of one gram of ginger per day. The research did not look at treatment approaches that involved drinking ginger tea or increasing the amount of ginger in the women’s diets.

As with acupressure, the research does not lead to a definite conclusion, so we are still not sure whether or not ginger can help reduce nausea in pregnancy. The trials of ginger use did not identify any adverse effects for the baby, but more research on this is needed. Ginger supplements can sometimes cause heartburn (indigestion) in pregnant women.

With no clear research results yet, paying attention to your body’s reactions to see what seems to help you could be a good idea. You can discuss when and what foods you can eat to relieve the symptoms with your doctor or midwife. If you are nauseous and you have to vomit often, it is important to drink enough fluids – especially water.

Author: German Institute for Quality and Efficiency in Health Care (IQWiG)

© IQWiG (Institute for Quality and Efficiency in Health Care)