MORNING SICKNESS

Morning sickness is a common symptom of early pregnancy and, in many cases, goes away by the end of the first three months. 

It is caused by changes in hormones during pregnancy and may make eating difficult. Although it is called 'morning sickness', nausea (with or without vomiting) can happen at any time of the day. Morning sickness does not usually cause any problems for the unborn baby. However, if a pregnant woman experiences severe and ongoing vomiting, it is important to contact a doctor.

Some food and eating suggestions that may help manage symptoms of morning sickness or nausea include:

• 
  Eat smaller meals more often. Missing meals can make nausea worse.
• Avoid large drinks. Have frequent small drinks between meals.
• Limit fatty, spicy and fried foods.
• Food has a stronger odour or smell when it is heated, which may make nausea worse. If possible, have other people help with cooking, or prepare your food at times of the day when you feel better.
• Try eating a dry biscuit before you get out of bed in the morning.
• Eat a healthy snack before you go to bed at night. This might include fruit (fresh, tinned, dried), crackers with hard cheese or yoghurt.
• Avoid foods if their taste, smell or appearance makes you feel sick.

If vomiting, it is important to drink enough fluids. It may be easier to have lots of small drinks than to try and drink a large amount in one go. Try a variety of fluids such as water, fruit juice, lemonade and clear soups. Sometimes it can be helpful to try crushed ice, slushies, ice blocks, or even suck on frozen fruit such as grapes or orange segments.

Note: The stomach acids in vomiting can soften teeth enamel. It is best not to use a toothbrush to clean the teeth straight after vomiting as this may damage them. Have a drink of water to clean your mouth. 

Don’t take medicines of any kind to treat your mornng sickness, unless your doctor knows you are pregnant and has prescribed specific medications.

Duration

Morning sickness usually starts to get better after the first three months of pregnancy. However, some women continue to experience nausea for a longer period. About 1 woman in 10 continues to feel sick after week 20 of their pregnancy. Morning sickness is sometimes considered to be a minor inconvenience of pregnancy, but it can have a significant, adverse effect on an expectant mother's day-to-day activities and quality of life. It can often be treated by making dietary changes and taking plenty of rest. The support of family and friends can also make morning sickness more manageable.

What causes morning sickness?

The exact cause of morning sickness is unknown. However, a number of different causes have been suggested, including: 

• increased oestrogen levels - changes in levels of the female sex hormone oestrogen during the early stages of pregnancy may cause short-term nausea and vomiting
• increased human chorionic gonadotrophin (hCG) levels - a hormone the body begins to produce after conception
• nutritional deficiency - a lack of vitamin B6 in the diet is thought to be another possible cause
• gastric problems - progesterone is a hormone that helps prepare the womb for pregnancy and protects the womb lining. As progesterone production increases, the movement in the small intestine, oesophagus (gullet) and stomach reduces, causing nausea. The reduction in movement occurs as a result of the muscle walls relaxing.

Risk factors

A number of different factors are associated with an increased risk of developing morning sickness. These include: 

• previous pregnancy with nausea and vomiting
• female foetus
• family history of morning sickness
• history of motion sickness
• history of nausea while using contraceptives that contain oestrogen
• young maternal age
• obesity
• stress
• multiple pregnancies, such as twins or triplets
• first pregnancy.

An enlarged placenta is also a known risk factor for morning sickness. The placenta is the organ that attaches the mother to her unborn baby and provides the baby with food and oxygen. 

The placenta can become enlarged in multiple pregnancies, such as twins or triplets, or during a molar pregnancy, where the fertilisation of the egg goes wrong and leads to an abnormal growth of cells inside the womb.

 

Department of health and ageing

NHS Choices (UK)