Nausea and vomiting in pregnancy, or NVP, is one of the most common ailments yet one of the least understood. It has not been subject to much research in terms of its causes or origins, complications and management.
The public and many in the medical community often do not understand how negatively it affects women's lives.
NVP is commonly referred to as "morning sickness" because symptoms tend to occur more often between 6 a.m. and noon, but symptoms may occur around the clock. About 75 percent of pregnant women experience it. More than 50 percent experience daily episodes of vomiting. In up to 40 percent of women, NVP interferes with family life, social interactions and employment.
Cases range from mild with mainly nausea, moderate with nausea and vomiting, or severe with dehydration. While fortunately rare, hyperemesis gravidarum involves persistent vomiting and weight loss, which usually requires hospitalization to correct dehydration and restore nutritional imbalances.
NVP is thought to result either from substances unique to pregnancy causing the nausea and vomiting or as a trait to protect the fetus from toxins ingested by the mother. Psychological and behavioral theories from years ago have been ruled out.
Management of symptoms depends on the individual because not all patients respond the same to treatment. In most pregnant women, NVP is temporary, peaking by weeks seven to 12 and resolving by week 16.
Symptoms usually can be managed with dietary and lifestyle changes. Suggestions include eating small frequent meals of high-carbohydrate and low-fat foods, and additional proteins; drinking plenty of liquids; getting adequate rest; avoiding caffeine, offensive odors and iron supplements; treating heartburn and delaying brushing teeth until after noon. Ginger, mint and orange tea might aid in digestion. Acupuncture and pressure-point wristbands also might be helpful.
When these fail, medication might be needed to prevent more serious complications. Patients and some physicians might fear possible birth defects will result despite evidence of safe and effective drug treatment regimens. These include anti-nausea drugs, antihistamines, antacids and steroids. Few new drugs have been developed to treat NVP.
If symptoms first appear after 10 weeks of pregnancy, they are commonly due to other reasons. A physical exam, history, laboratory and ultrasound evaluation might be needed. Early diagnosis and intervention are important to improve the quality of the woman's life and to decrease complications for the mother and baby.