Morning sickness is also known as nausea gravidarum, nausea/vomiting of pregnancy (NVP), emesis gravidarum, and pregnancy sickness. For many women, the symptoms of morning sickness are their first signs of pregnancy.
In the vast majority of cases, morning sickness, although an unpleasant experience, has no health risk for the baby and is a regular part of pregnancy. In fact, some studies indicate that morning sickness during pregnancy can be a sign of a healthy pregnancy, with lower rates of miscarriages and stillbirths, compared with pregnancies with no nausea or vomiting.
Fast facts on morning sickness
Here are some key points about morning sickness. More detail and supporting information is in the main article.
- Morning sickness can occur at any time of the day or night.
- The exact causes are still not known.
- There are a number of home remedies that can help treat the symptoms of morning sickness.
- A small amount of evidence suggests that ginger might ease the nausea.
- Morning sickness may be a sign of a healthy pregnancy.
Morning sickness treatment
Ginger is commonly used to relieve nausea and vomiting, often in the form of ginger lozenges or candies.
For most cases of morning sickness, treatment by a doctor is not necessary. However, there are some things that might alleviate symptoms. A full list of these can be found in our article top tips to minimize morning sickness. However, here are a few ideas:
Rest - tiredness can make nausea worse. Getting plenty of rest is vital.
Liquids - fluid intake should be regular and in small amounts, rather than less often and in large quantities. This may help reduce vomiting. Sucking ice cubes made from water or fruit juice or trying lollipops can help.
Food - consuming more meals per day, with smaller portions may help, especially high-carbohydrate meals. Dry and savory foods, such as crackers or crispbread are usually better tolerated than sweet or spicy foods. Cold meals are often better tolerated than hot ones because they have less odor.
Empty stomach - pregnant women with morning sickness should try to avoid having an empty stomach.
Early morning - many women find that eating plain biscuits about 20 minutes before getting up helps.
Triggers - it does not take long to identify nausea triggers. Avoiding them helps reduce the frequency and severity of nausea and vomiting.
Medical treatment - if symptoms are still severe, despite attempting self-care measures, the doctor may recommend a short course of anti-sickness medication (antiemetic), which is safe to use during pregnancy.
Ginger supplement - some studies have shown that ginger supplement may help reduce nausea symptoms during pregnancy. Women should purchase this from a reputable source.
B-6 and doxylamine - this combination is sold over the counter as Unisom SleepTabs. It has been recommended by the American College of Obstetricians and Gynecologists for treating morning sickness during the first trimester. Trials have found this combination to be effective at reducing nausea and vomiting in up to 70 percent of cases. Side effects include drowsiness, dry mouth, headache, nervousness, and stomach pain.
Diclegis - this drug is FDA-approved for use by pregnant women. One clinical trial found that Diclegis completely relieved nausea in 44 percent of women with morning sickness. Another study found that more than 70 percent of women reported improvements in symptoms.
Acupressure - this is the application of pressure on specific points on the body to control symptoms. It involves wearing a special band (sometimes called a sea-band) on the forearm. Some limited evidence suggests that this may help improve nausea and vomiting symptoms in pregnant women, although large-scale trials are lacking.
Causes of morning sickness
Morning sickness is most common during the first trimester of pregnancy.
The exact causes of morning sickness are still not known; however, most agree that hormonal changes probably play a role:
Estrogen levels - experts believe it might be partly due to an increase in the circulating level of estrogen, which can be 100 times higher during pregnancy, compared with levels found in women who are not pregnant. However, there is no evidence to show a difference in estrogen levels between pregnant women with or without morning sickness.
Progesterone levels - when a woman is pregnant, her levels of progesterone also rise. High levels of progesterone relax the uterus (womb) muscles to prevent early childbirth. However, it may also relax the stomach and intestines, resulting in excess stomach acids and GERD (gastroesophageal reflux disease, or acid reflux).
Hypoglycemia - low blood sugar, caused by the placenta draining energy from the mother's body. However, there are no studies to prove this.
Human chorionic gonadotropin (hCG) - this hormone is first produced by the developing embryo soon after conception and then later by the placenta. Some experts suggest there may be a link between hCG and morning sickness.
Sense of smell - during pregnancy, there may be an increase in sensitivity to odors, which might overstimulate normal nausea triggers.
Morning sickness as an evolutionary survival adaptation
Some experts suggest that morning sickness could be an evolutionary adaptation that protects pregnant mothers and their babies from food poisoning. If the woman with morning sickness does not feel like eating foods, which may be potentially contaminated, such as poultry, eggs, or meat, and prefers foods with a low contamination risk, such as rice, bread, and crackers, the survival chances for her and her child are improved.
Adult humans have defenses against plant toxins, including a wide range of detoxification enzymes produced by the liver. In the developing baby, these defenses are not yet fully developed, and even relatively small amounts of toxins could be harmful.
The baby's developing organs are most vulnerable to toxins between 6-18 weeks, more or less the time when morning sickness peaks.
Morning sickness symptoms
Despite its name, morning sickness can come on at any time of day. For some people it strikes in the middle of the night.
Morning sickness may include nausea and vomiting, or just nausea without vomiting. It is much more common during the first trimester of pregnancy.
Pregnant women should call their doctor if:
- symptoms of nausea or vomiting are severe
- they pass only a small amount of urine
- their urine is a dark color
- they cannot keep liquids down
- they feel dizzy when they stand up
- they faint when they stand up
- their heart races
- they vomit blood
When symptoms are very severe, the condition is called hyperemesis gravidarum, which develops in approximately 1-2 percent of all pregnancies.If nausea and vomiting occur, it is usually during the 6th week of pregnancy.
Most pregnant women find that morning sickness improves after the 12th week of pregnancy. Unfortunately, for some, symptoms persist throughout the entire pregnancy.
Some dietary changes and getting plenty of rest are usually all that is needed to treat morning sickness. Although viewed romantically and humorously, morning sickness can seriously affect the mother's quality of life and how she goes about her daily activities. Women who receive support from family and friends tend to cope much better.
Morning Sickness: Risk factors and complications
Hyperemesis gravidarum is a very rare but severe form of morning sickness, which is thought to affect about 1-2 percent of all pregnant women. In 90 percent of hyperemesis gravidarum cases, symptoms go away by the fifth month of pregnancy.
Typically, severe symptoms include:
- cannot keep fluids down because of severe vomiting
- serious risk of dehydration and weight loss
- alkalosis (a dangerous drop in the normal acidity of the blood)
- hypokalemia (low blood potassium)
Women with severe symptoms should seek medical help immediately. In some cases, hospitalization and treatment with intravenous fluids may be necessary.
If a woman has hyperemesis gravidarum, the chances of causing harm to the baby are very small. If she experiences weight loss during pregnancy, there is an increased risk of giving birth to a baby of low birth weight.
Any woman who is pregnant has the potential for developing morning sickness. However, the risk is higher if:
- before the pregnancy, the woman had experienced nausea or vomiting from motion sickness, migraines, some tastes or smells, or birth control pills
- the mother had experienced morning sickness in a previous pregnancy
- the mother is expecting more than one baby
Diagnosing morning sickness
Diagnosis of morning sickness is usually a straightforward question of identifying the hallmark symptoms.
If hyperemesis gravidarum is suspected, the doctor may order various urine and blood tests. An ultrasound scan might also be done to confirm the number of fetuses and to look out for any underlying conditions that could contribute to nausea and vomiting.
If ketone levels in the urine are found to be high, it is possible that the vomiting is causing the mother to become malnourished.