The term “stomach flu” describes acute gastroenteritis, an inflammation of the stomach and intestines most often caused by a viral infection like norovirus or rotavirus. While unpleasant during pregnancy, the condition is usually short-lived and manageable at home. The infection itself rarely poses a direct threat to the developing fetus because the virus typically does not cross the placental barrier. The primary concern is the body’s reaction to the illness, specifically the risk of rapid fluid loss.
Viral Gastroenteritis and Pregnancy Risks
Viral gastroenteritis must be distinguished from true influenza, which is a respiratory illness. True influenza is a more serious concern during pregnancy due to increased risks of complications like pneumonia. In contrast, viral gastroenteritis focuses on the digestive tract, presenting with symptoms such as nausea, vomiting, watery diarrhea, abdominal cramping, and sometimes a low-grade fever.
The primary risk to the pregnant person is severe dehydration resulting from fluid loss through vomiting and diarrhea. During pregnancy, the body’s fluid needs increase significantly, making the person more susceptible to dehydration. When the body loses too much water and electrolytes, the total blood volume can decrease, which affects circulation.
Severe dehydration can reduce blood flow to the uterus, temporarily limiting the supply of nutrients and oxygen to the developing baby. In the second and third trimesters, this fluid imbalance can also trigger uterine irritability. This may lead to painful Braxton Hicks contractions or, in severe cases, preterm labor. Prolonged dehydration can also decrease the volume of amniotic fluid, which is essential for cushioning the baby and supporting lung development.
Safe Strategies for Home Recovery
Managing symptoms at home focuses on preventing dehydration and resting the digestive system. Consistently replacing lost fluids and electrolytes is crucial, even when it is difficult to keep anything down. Oral Rehydration Solutions (ORS) are highly recommended instead of plain water, which can dilute the body’s remaining electrolytes.
ORS should be sipped in very small, frequent amounts, perhaps just a teaspoon every few minutes. Attempting to drink a large volume at once is discouraged. Large quantities of fluid can stretch the stomach, often triggering another round of vomiting.
Once vomiting has stopped for several hours, slowly reintroduce bland, easy-to-digest foods to restore energy. The traditional BRAT diet—bananas, rice, applesauce, and toast—offers binding, low-fiber foods gentle on the intestinal lining. Avoid rich, high-fat, high-sugar foods, dairy products, and caffeine, as these can irritate the digestive tract.
Acetaminophen is used to manage fever or body aches during pregnancy. However, many other over-the-counter medications, including anti-diarrheal or anti-nausea drugs, may be restricted or unsafe. A pregnant person must consult with a healthcare provider before taking any medication to confirm it is appropriate for use.
Warning Signs Requiring Medical Care
Most cases of viral gastroenteritis resolve within 24 to 48 hours, but specific warning signs require immediate medical attention. The most common indicator that home management is failing is the inability to keep any fluids down for more than 12 hours.
Signs of severe dehydration include producing very dark, concentrated urine or not urinating at all for eight hours or more. Physical symptoms include dizziness, lightheadedness, a rapid heart rate, or confusion. Any combination of these symptoms means a trip to a clinic or hospital is necessary to receive intravenous (IV) fluids.
Other urgent symptoms relate to the severity of the infection or potential complications. These red flags include:
- A fever that remains elevated above 101.5°F despite using Acetaminophen.
- Severe, sharp abdominal pain that is more intense than typical cramping.
- The presence of blood in either the vomit or the stool.
- Any noticeable decrease in fetal movement during the second or third trimester.
Medical professionals will assess hydration levels and may run blood tests to check electrolyte balance and kidney function. In the event of severe dehydration, receiving IV fluids and prescription anti-nausea medication allows the body to rehydrate quickly. Seeking care promptly for these severe symptoms helps stabilize the pregnancy and prevents a temporary illness from leading to a serious complication.