Nausea and vomiting during pregnancy

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Nausea and vomiting is experienced by 50-80% of women during the first trimester of pregnancy. It can have a serious impact on the day-to-day lives of women and can usually be treated, with varying degrees of success.

What causes nausea and vomiting during pregnancy?

It is not known why women experience nausea and vomiting during the first 16 weeks of pregnancy. Nausea may be related to low blood sugar levels, low levels of vitamin B6, a hormonal imbalance, or an imbalance in potassium and magnesium. However, a well balanced diet should provide all of these vitamins and minerals.

Nausea is more common and severe in pregnancies with higher human chorionic gonadotrophin (HCG) levels. HCG is a hormone produced in pregnancy; pregnancy tests use this as a marker to indicate pregnancy. Higher HCG levels are common in multiple pregnancies and molar pregnancies. Molar pregnancies are very rare, approximately 0.1% of pregnancies and is basically when a pregnancy does not form properly and does not continue.

Generally the nausea occurs during the morning; hence it is also called morning sickness. Unfortunately some women will still experience nausea during the afternoon or evening.

Severe vomiting in pregnancy is very rare. It only occurs in about one in 1000 pregnancies and is called hyperemesis gravidarum.

How can I reduce nausea and vomiting?

Some practical ways to reduce nausea and vomiting during pregnancy include:

  • not over-eating;
  • eating smaller meals, more often, such as every two or three hours;
  • having a snack of yoghurt, milk, juice bread or a sandwich before bed, can help reduce nausea in the morning. You may need to sit upright for 10 to 20 minutes after eating to prevent gastric reflux;
  • having a biscuit or two whilst still in bed in the morning three hours;
  • getting out of bed slowly to avoid sudden movement;
  • drinking soups and other liquids between meals. Instead of drinking fluids with meals, drink them about half an hour after the meal. This may help reduce the distension and swelling of the stomach that can trigger vomiting;
  • avoid greasy or fried food, they are hard to digest and can worsen nausea, and
  • getting plenty of fresh air. Take a short walk or try sleeping with the window slightly open. To help get rid of odours, open the windows and use the exhaust fan when you are cooking.

Can taking ginger reduce nausea and vomiting?

Research has shown that half a capsule of Zinax, which is used for arthritis, taken four times a day, can reduce nausea. Each capsule contained 1.5 grams of dried ginger. Other studies have shown that one gram of dried ginger can reduce nausea. Ginger capsules are available from natural therapy stores.

Can acupuncture help?

Some trials have shown that acupressure and acupuncture, on the point known as pericardium 6 (p6) located on the underside of the wrist, were associated with significant improvements in nausea by the end of one week and dry retching by two weeks compared to no treatment. There was no improvement in vomiting.

Another trial of acupressure wrist bands, commonly referred to as sea-bands, demonstrated a considerable effect in reducing nausea and vomiting in early pregnancy.

There are also acupressure wrist devices which use an electrical current and have been shown to achieve positive results in reducing nausea and vomiting in patients who have undergone chemotherapy and in post-operative recovery.

What else can be taken to reduce nausea and vomiting?

There are several medications which can alleviate nausea and vomiting during pregnancy and your doctor can advise which may be suitable for you.

Two common medications which can be effective are:

  • doxylamine succinate, the active ingredient found in anithistamines such as Dozile, and
  • metoclopramide hydrochloride, the active ingredient found in Maxolon.

The antihestamine generally needs to be taken of a night due to its sedating effects. Many women find this medication helpful and it also assists in gaining a good nights sleep, which can help your body cope with the nausea.

Both of these medications are Category A, which means they have been taken by large numbers of people, including pregnant women, with no proven links to adverse impacts on the fetus.

Stemetil and Ondansetron (Zofran) may also be effective. Zofran can be taken as a wafer and placed under the tongue, which can be helpful for women who are finding it difficult to swallow anything.

I am unable to eat much due to nausea, if I am not reaching my dietary requirements could this harm my baby?

We have evolved so that pregnancies can survive famines, so the body copes very well if your food intake is restricted temporarily. The baby is able to absorb everything it needs from its mother’s body.

If you had a good diet before pregnancy, your body will generally have plenty of vitamins and minerals for the healthy growth and development of your baby. The nausea is generally confined to the beginning of the pregnancy and once alleviated you will be able to resume a well balanced diet.

If you are experiencing more extreme vomiting, you may need to be hospitalised and be placed on intravenous fluids. Please speak to your doctor if your nausea is severe.