Nausea and vomiting in pregnancy is very common in the first trimester. About 4 in 5 women experience it. It usually occurs in the morning and is therefore often called “morning sickness.” However, in a minority of women, the nausea is more severe in the afternoon.
It usually starts when you are about 6 to 7 weeks pregnant and begins to improve when you are about 10 to 12 weeks pregnant. In some women the symptoms can continue for longer than that, but nausea seldom lasts beyond 20 weeks gestation.
Most women who experience it in the beginning of the pregnancy will often have some returning nausea at the end of the pregnancy. Nausea during pregnancy is more severe if it runs in your family or if you are carrying twins.
The cause of the nausea is probably a result of a heightened sense of smell, accompanied by elevated pregnancy hormones such as Human Chorionic Gonadotropin (HCG), which peaks at about 10 to 12 weeks gestation.
It is important to realize that typical pregnancy nausea and vomiting will not affect your baby’s health. If your symptoms are severe, it is easy to become dehydrated, which will often make you feel even worse. Signs of dehydration are fatigue, dry tongue, infrequent urination, and dark-colored urine.
If you also develop heartburn, it can make the nausea worse. If this occurs, talk to your health care provider about taking Tums® or Ranitidine (Zantac®) to ease the heartburn.
There are many things you can do to decrease the nausea. You can eat and drink small portions (such as sport drinks and crackers) during the times when you are feeling well. You can also temporarily substitute your large prenatal vitamin for a 0.4 mg folic acid (folate) pill, which is easier on your stomach.
Many women find acupressure is helpful. You can also take vitamin B6 supplements (25 mg 2-4 times per day). In some countries, you can buy over-the-counter Benedictin (Diclectin®) which is a combination of an antihistamine Doxylamine and vitamin B6. In the US it is sold as prescription medication and is called Diclegis®.
Some pregnant women have also noted relief with mint candies, chewing gum, ginger, lemon flavored water, lavender aromatherapy oil, and papaya tablets. If your nausea is severe, talk to your health care provider about anti-nausea medications.
Promethazine (Phenergan®) and Ondansetron (Zofran®) are often prescribed. They might make you sleepy and/or cause constipation. Ondansetron (Zofran®) has been recently been loosely linked to possible birth defects by some smaller studies. Other studies have not shown any association, however. Talk to your Medical health provider about the drug if you are planning to use it.
Other medications might be suggested if the nausea does not abate. Frequent intravenous fluid administration along with vitamins might also be recommended if your symptoms are severe and you are becoming very dehydrated.
Hyperemesis Gravidarum is a severe form of “Nausea and Vomiting of Pregnancy” that often lasts for the duration of the pregnancy. It can cause extreme dehydration and severe health problems. If you feel your situation is very severe, contact your health care provider immediately.