Fainting

Fainting during pregnancy: Causes and first aid

Short‑term loss of consciousness, or fainting (syncope), is one of the most frightening symptoms a future mother may encounter. Although in most cases the causes are physiological and not dangerous, every episode of fainting during pregnancy requires mandatory consultation with a doctor to rule out serious conditions.

Why does it happen?

The basis of fainting is a temporary reduction in blood flow to the brain. During pregnancy, a whole range of factors contributes to this:

• Low blood pressure. Hormone‑induced vessel dilation and orthostatic hypotension (sudden drop in pressure upon standing) are the main cause.
• Low blood sugar (hypoglycemia). Skipping a meal can lead to a drop in glucose level, which is the "fuel" for the brain.
• Dehydration. Insufficient fluid intake reduces circulating blood volume.
• Overheating. Prolonged stay in a hot, stuffy environment or a hot bath dilates peripheral vessels, causing blood to "pool" away from the brain.
• Compression syndrome of the inferior vena cava. Lying on the back in late pregnancy can cause this condition.
• Anemia. A lack of hemoglobin means blood carries less oxygen, making the brain more sensitive to any fluctuations in blood flow.

Prevention and initial actions

Knowing the causes allows effective prevention of fainting. It is important to avoid sudden movements, eat frequently, drink enough water, and not stay long in stuffy rooms. If you feel you are about to faint (sudden weakness, "tunnel vision", ringing in the ears), you should immediately sit or lie down, lowering your head below heart level. Read more about pregnancy complications and alarming symptoms on our website.