What is morning sickness?
Morning sickness, the well-known nausea that some women have when pregnant, is not as predictable as the name implies. You might have it in the morning, on and off during the day or constant - all day. It might last a few weeks or throughout your pregnancy. You might feel a little queasy or you might have severe nausea and vomiting.

No one knows exactly what causes morning sickness. Hormonal changes early in pregnancy are believed to play a large role. Estrogen is thought to cause nausea and regurgitation of stomach acids in some women. Other possible causes include changes in blood sugar, slowed digestion and an increase in your sensitivity to smells. Some researchers suggest that nausea is your body's way of protecting the fetus from things that could be dangerous. For example, nausea may keep many pregnant women away from coffee, alcohol and cigarette smoke that may turn their stomach. Your symptoms can be made worse by hunger, fatigue, prenatal vitamins and other factors.

How long will it last?
About a third to half of all pregnant women have morning sickness only in the early weeks of pregnancy. For many, morning sickness disappears by the second trimester (the fourth month). Some women, though, have morning sickness all through their pregnancy, right up till delivery.

Is my nausea bad for my baby?
Morning sickness doesn't generally harm the fetus. Many doctors think morning sickness is a healthy sign because it means the placenta and fetal membranes are developing well. And, more interestingly, women with morning sickness miscarry less often. But it can become a problem if you can't keep enough foods or fluids down and you start to lose weight and/or become dehydrated. This can deprive the fetus of needed nutrition.

When should I call the doctor?
Talk to your doctor if morning sickness is severe or lasts past the first three months of pregnancy, causes you to lose weight, makes you dehydrated, or keeps you from doing the things you need to do on a daily basis.

Seek immediate medical care if you have any of the following symptoms:

• You feel faint, lightheaded or dizzy.
• You have blood in your vomit.
• You have signs of dehydration: dry mouth, little or no urine.
• You have a fever higher than 102 degrees F.
• You have abdominal pain.

Are there tips for coping with morning sickness?
Yes, there are. Not all of them work for every woman, but you might want to try these home remedies:

• Eat crackers before you get out of bed each morning.
• Eat small meals throughout the day so that you never have an empty stomach and you are never too full.
• Avoid rich, fatty foods.
• Avoid foods or smells that bother you.
• When you feel nauseous, eat bland foods, such as a plain baked potato, white rice, dry toast, noodles, unbuttered cooked vegetables, a poached egg or light soups.
• Try frozen fruit bars, decaffeinated tea and pretzels.
• Suck on hard candy.
• Try eating or drinking something with ginger, which can be settling to the stomach. (Non-diet ginger ale, ginger tea or ginger snaps.)
• Consider wearing an acupressure band on your wrist(s). These bands are available in drug stores and are commonly used for motion sickness.

Are there any medicines for morning sickness?
The American College of Obstetricians and Gynecologists (Healthlinerx) has guidelines for morning sickness meds. They state that the use of either vitamin B-6 alone or together with doxylamine (Unisom) is safe and effective for nausea from morning sickness. If home treatments don't help, ask your doctor if you can try vitamin B-6 with doxylamine.

In cases of severe morning sickness, intravenous fluids and anti-nausea medications can be given to prevent vomiting and dehydration. These can be given in the hospital or at home.