Morning sickness

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Morning sickness, also called nausea, vomiting of pregnancy (emesis gravidarum or NVP), or pregnancy sickness, affects between 50^[1] and 95 percent of all pregnant women as well as some women who use hormonal contraception or hormone replacement therapy. The nausea can be mild or induce actual vomiting. In extreme cases, known as hyperemesis gravidarum, hospitalization may be required to treat the resulting dehydration, which occurs in about 1% of pregnancies.

Contents 1 Duration of condition 2 Causes 3 Treatments 3.1 Thalidomide tragedy 3.2 Research 4 Associations with miscarriage risk 5 References 6 External links

[edit] Duration of condition

Morning sickness can occur at any time of the day, though it occurs most often upon waking, because blood sugar levels are typically the lowest after a night without food.

Morning sickness usually starts in the first month of the pregnancy, peaking in the fifth to seventh weeks, and continuing until the 14th to 16th week. For half of the sufferers, it ends by the 16th week of pregnancy. It may take the others up to another month to get relief, and some women suffer intermittent episodes throughout their pregnancy.

[edit] Causes

There is insufficient evidence to find a single (or multiple) cause, but the leading theories for proximate causes include:

• An increase in the circulating level of the hormone estrogen. Estrogen levels may increase by up to a hundredfold during pregnancy.
• Low blood sugar during pregnancy.
• An increase in progesterone relaxes the muscles in the uterus, which prevents early childbirth, but may also relax the stomach and intestines, leading to excess stomach acids.
• An increase in human chorionic gonadotropin.
• An increase in sensitivity to odors, which overstimulates normal nausea triggers.
• An increase in bowel movement.
• The body's effort to detoxify thoroughly for the health of the unborn child. This is supported by evidence that the liver and kidneys become more active than usual at the start of a pregnancy.

As for root causes, this issue is still somewhat controversial. A notable current scientific hypothesis is that morning sickness exists as a safeguard for the embryo's health. Biologists Gillian V. Pepper and S. Craig Roberts have done a study that indicates that the intake of alcohol, sugar, oils, and meat can trigger morning sickness. This then acts as a way of discouraging ingestion of less healthy foods.^[2]

Although Margie Profet has argued that eating vegetables may be a factor as well,^[3], this idea has been rejected by a prospective, population-based study which concluded that "claims made in the popular press about food and health relationships should be evaluated by the media as fiction unless supported by scientific research".^[4] Both Profet's vegetable theory and Deutsch's suggestion morning sickness's role is to reduce frequency of sexual intercourse, so preventing sexual uterine cramping that might be a cause spontaneous abortion,^[5] have been rejected by a cross-cultural study that suggested morning sickness is more frequently observed in societies that have animal products as dietary staples which may "be dangerous to pregnant women and their embryos because they often contain parasites and pathogens" and hence "that morning sickness serves an adaptive, prophylactic function".^[6]

[edit] Treatments

Treatments for morning sickness typically aim to lessen the symptoms of nausea, rather than attacking the root cause(s) of the nausea. Treatments include:

• Lemons, particularly the smelling of freshly cut lemons.
• Avoiding an empty stomach.
• Accommodating food cravings and aversions.
• Eating five or six small meals per day, rather than three large ones.
• Many sources recommend Cabbage.^[7][8]
• Trying the BRATT diet: bananas, rice, applesauce, toast and tea.^[9]
• Ginger, in capsules, tea, ginger ale, or ginger snaps.^[10]
• Eating dry crackers in the morning.
• Drinking liquids 30 to 45 minutes after eating solid food.
• Vitamin B6 (either pyridoxine or pyridoxamine), often taken in combination with the antihistamine doxylamine (Diclectin).

A doctor may prescribe anti-nausea medications if the expectant mother suffers from dehydration or malnutrition as a result of her morning sickness, a condition known as hyperemesis gravidarum. In the US, Zofran (ondansetron) is the usual drug of choice, though the high cost is prohibitive for some women; in the UK, older drugs with which there is a greater experience of use in pregnancy are preferred, with first choice being promethazine otherwise as second choice metoclopramide, or prochlorperazine.^[11]

[edit] Thalidomide tragedy

Further information: Thalidomide#History

Thalidomide was originally developed and prescribed as a cure for morning sickness in West Germany, but its use was discontinued when the drug's teratogenic properties came to light. The United States Food and Drug Administration never approved thalidomide for use as a cure for morning sickness.

[edit] Research

A recent Canadian survey conducted by researchers at the University of British Columbia and the University of Victoria suggested that the use of medical marijuana may be effective in combating morning sickness,^[12] although the researchers noted that their survey was not conclusive.^[13]

[edit] Associations with miscarriage risk

Studies have shown that women who suffer from morning sickness are less likely to have miscarriages as well as less likely to give birth to a baby with birth defects.^[14] Other doctors disagree with these links and claim that the mother's sensitivity to the changes in her body is not a variable that indicates risk of miscarriage.^{[citation needed]} It is also mentioned that many women having a molar pregnancy or an ectopic pregnancy suffer strong nausea.

[edit] References

[edit] External links

• Help and medical advice about nausea and vomiting of pregnancy, NVP