Is Morning Sickness Constant?

Why Morning Sickness Occurs

• Pregnancy causes a seismic shift upward in certain hormones, which appear to contribute to morning sickness. The jury is still out on exactly which hormones cause morning sickness; researchers often disagree on the culprit. Pediatrician Dr. William Sears points to rising levels of thyroid hormone and human chorionic gonadotropin -- the hormone measured in urine and serum pregnancy tests -- as the cause of morning sickness. The dominant female hormone estrogen, prolactin and progesterone, produced by the forming placenta, could also play a role in morning sickness. Low blood glucose levels could also influence who gets morning sickness.

Its Usual Duration

• Morning sickness isn't set on a timer to start precisely at 5 a.m. and to end at noon, or to start at five weeks of pregnancy and end at the 14th week. You might wake up sick every day for a week and then, inexplicably, have a day completely free of morning sickness, only to have it recur a few days later. As many as 90 percent of all women experience some nausea -- with or without vomiting -- starting as early as the fourth week -- around the time of the first missed period -- and, in some cases, this lasts up until the day of delivery. For most women, morning sickness develops between weeks four and six and ends between the 14th and 16th weeks, states the University of Maryland Medical Center.

Morning Sickness Risks

• Having morning sickness can wreak havoc with your work attendance and make your life miserable, but -- unless it's severe -- it won't harm you or your baby. Morning sickness that affects your ability to stay hydrated or to obtain the nutrition you need, called hyperemesis gravidarun, occurs in just 0.5 to 2 percent of women, according to the Lucile Packard Children's Hospital at Stanford. If you can't keep any food down at all, lose more than two pounds, or vomit dark, coffee ground-like material, see your doctor. You might need intravenous therapy in the hospital to get you through the worst part of severe morning sickness.

The Good Side of Morning Sickness

• Some positive things do exist about morning sickness, although you might have trouble appreciating them when you're spending the morning in the bathroom. Morning sickness often indicates a robust, healthy pregnancy, a Cornell University review of studies published in the June 2000 "Quarterly Review of Biology" reported. Women who experience morning sickness have a lower rate of miscarriage than women who don't have morning sickness. Morning sickness might also act as a protective mechanism, in protecting pregnant women from potentially harmful pathogens and toxins.

Combatting Morning Sickness

• You don't have to suffer stoically through morning sickness. You can decrease its effect by eating something before you get out of bed, by eating every few hours or by eating a small snack before bedtime. Ginger products such as ginger tea or ginger soda might also help settle your stomach. Alternatively, you can buy a hand of ginger root at the store and add it to plain seltzer, juice or herbal tea, as well.