One of the classic symptoms of early pregnancy is nausea or morning sickness. Some women experience morning sickness even before they have had their pregnancy confirmed. And even if it's too early after conception for a pregnancy test to show a positive result, morning sickness can still raise suspicions for some women.
Morning sickness is so common that around half to two thirds of pregnant women will experience it in some form. However, the term morning sickness is not really a good name because it is rarely restricted to just the early hours of the day. Around half to two thirds of pregnant women will experience some degree of morning sickness. Even women who've had morning sickness previously are not pre-destined to have it again with subsequent pregnancies.
Despite the high incidence of morning sickness, some pregnant women will never experience a moment of it. An absence of morning sickness can be completely normal and is not a sign that you are somehow less pregnant than women who do have it. Similarly, when women have experienced a high level of morning sickness, they can worry when it goes away.
Morning sickness can come and go with little warning or explanation. Some days you may feel just fine and others will be a struggle.
Will it harm the baby?
Many women worry that their nausea and vomiting will adversely affect their developing baby.
With so much emphasis on proper nutrition and its importance during pregnancy, it's normal for pregnant women to worry their baby be getting all the required nutrients. Try not to be concerned. Nature can be very protective. Unless you are experiencing extreme nausea, weight loss and/or are dehydrated, your baby will be getting what it needs, when it needs it.
Only in the most extreme cases of vomiting and food intolerances, is there a potential risk to the baby. Speak with your maternity care provider who knows you and your individual history.
Some women experience morning sickness in combination with other early pregnancy symptoms. Bloating, constipation, heightened sense of smell and emotional ups and downs. There is no one consistent pattern regarding how morning sickness affects individual women. For an unfortunate few, morning sickness does not settle after the third trimester is over and continues into the second and even third trimesters.
Why does it occur?
- There is a link between not eating frequently enough and low blood sugar causing morning sickness.
- The vomiting centre in the brain can become highly sensitive, making certain foods, smells, textures and even the thought of some foods result in vomiting.
- Possible fluctuations in blood pressure (BP) especially when it is low.
- High levels of pregnancy hormones, specifically oestrogen and hCG (human Chorionic Gonadotrophin) cause morning sickness to occur. These are particularly high in the first trimester of pregnancy when they play a vital role in supporting the newly fertilised egg.
- Progesterone, another hormone which is high in pregnancy, causes the muscles of the digestive tract to relax. This means the stomach contents can easily regurgitate up out of the stomach and into the oesophagus (food pipe).
- There may be a genetic influence for some women. Those whose mother experienced morning sickness appear to have a higher tendency for it as well.
The benefits (Yes there are some)!
- From a biological point of view, morning sickness can be protective to the foetus. Being able to tolerate only bland, simple foods means that mothers may then reduce the risk of being exposed to food-borne diseases.
- Women who experience morning sickness are thought to be at less risk of miscarriage. Their pregnancy hormones may be so high that it is thought they play a protective role in maintaining their early pregnancy. However, it's important to understand that in the absence of morning sickness, pregnancy is less likely to continue. Every woman and her pregnancy are unique.
Morning sickness is more common in:
- First pregnancies
- Multiple pregnancies such as twins, triplets or more
- The first trimester (first 12-14 weeks)
- Women who are prone to motion sickness or sea sickness
- Women who are fatigued and exhausted
- Periods of stress
What can help?
- Time and patience. In most women, it eases by around 14 weeks of gestation.
- Don t force yourself to eat particular foods just because you feel you should. As long as what you are eating is safe, eat when you feel you can best tolerate food.
- Avoid strongly flavoured or scented foods if you're feeling nauseous. Try to stick with bland, easy to digest foods which don t require much preparation.
- Foods served cold or cool foods like salads, yoghurt, fruit and even cold soups may be more palatable to you. Hot foods tend to emit more odours.
- Try eating small amounts frequently. High carbohydrate foods like bread, rice, pasta and potatoes are usually well tolerated. Dry crackers with a salty spread are usually fine, so are basic cereals with low fat milk.
- Avoid eating large amounts of food, especially if you feel as if you are starving. It will take around 20 minutes for your brain to register that your stomach is full, so stop eating when you feel as if you are almost satisfied.
- Keep a glass of water and some dry biscuits beside your bed. Before you even put your feet on the floor in the mornings, sip some water and munch on a couple of crackers. Avoid having a completely empty stomach if you can.
- Some women find that using acupressure bands on their wrists work very effectively. Check with your pharmacist about how and where to apply these for maximum effectiveness.
- Try drinking ginger beer/ale, eating ginger sweets, ginger biscuits or plain crystallised ginger. Cutting up a piece of raw ginger and inhaling its scent may be soothing as well.
- Lemonade, freshly squeezed juice, or mixed through soda water with crushed ice can help to combat queasiness.
- Keep some barley sugar sweets close by. Eating a couple will give an immediate boost to your blood sugar and may help ward off feelings of nausea. Some women find fruit flavoured chewable jubes equally as good.
- Try brushing your teeth and tongue if you're feeling sick. Some women develop a hypersensitive gag reflex and have problems even brushing their back molars. Experiment with alcohol-free mouthwashes, especially if you are bothered by a metallic, sharp taste in your mouth. Sipping iced water and munching on ice chips can have the same refreshing effect.
- Avoid strongly scented perfumes, deodorants, air fresheners and detergents. Open windows when you can and avoid sitting in stale, stuffy environments. Go for a walk where possible and fill your lungs with fresh air.
When do I need to be concerned?
- If you get to the point of vomiting so severely that you cannot keep any food or fluids down, you will need to see your maternity care provider. Dehydration can lead to an electrolyte and mineral deficiency. Blood pressure can also drop, requiring hospitalisation and intravenous fluids.
- Around 1 3 percent of women develop Hyperemesis Gravidarum. Occasionally, it becomes necessary for a doctor or obstetrician to prescribe anti-nausea medication. While this is best avoided whenever possible, prescribed medications have been rigorously tested for any potentially dangerous side effects to both the mother and her baby.
Edited and reviewed by Jane Barry, Midwife and Child Health Nurse July 2021.
Last Published* July, 2024
*Please note that the published date may not be the same as the date that the content was created and that information above may have changed since.