Becoming pregnant starts a series of changes which affects every system in the body. In order to adapt and provide the capacity to nurture a growing embryo, remarkable adjustments take place, some of which, will alter the ability to cope with balance challenges that are usually dealt with easily.
Many pregnant women will describe a light headed feeling or occasional dizziness. This tends to be related to the fact that the cardiovascular system is working harder than usual. The heart is beating faster and blood pressure is reducing. These changes can affect the nervous system so that oxygen is not always delivered to the balance centres in sufficient quantities. This leads to spells of dizziness or vertigo.
When am I likely to feel dizzy or lightheaded?
Standing up suddenly can produce unexpected dizziness. This is particularly the case if sitting in a warm environment for a prolonged period. Low blood pressure together with pooling of blood in the large vessels of the legs produces a short term lack of blood flow to the brain on standing. This has been described as pre-fainting, dizziness on standing, and lightheadedness. The best treatment is to lie down. The problem will then pass quickly. To avoid the problem, it is best to rise slowly from a sitting or lying positon, with support when needed.
As the baby grows, it asks more and more of its mother. In addition to its nutritional needs however the baby's position means that it can sometimes press on the large vessels in the abdomen returning blood to the heart. Women in the the third trimester may sometimes find themselves in an odd situation in which lying down if they feel faint, doesn't help. This is because lying on your back with a baby pressing down on the blood vessels of the abdomen can reduce blood flow to the heart and then on to the brain. An easy solution is to adjust to lying on the side. The problem will quickly resolve.