Dizziness can be an early sign of pregnancy, but it is unlikely to occur in the first week of pregnancy. Dizziness during pregnancy may be due to reduced blood pressure, morning sickness, blood vessel changes, and more.

It is worth keeping in mind that doctors calculate pregnancy from the first day of the last menstrual period, rather than conception. A person may not be pregnant during the first week of this time frame.

This is because pregnancy really begins with implantation — the fertilized egg embedding in the uterus — which takes place 8–10 days after ovulation.

It is only after implantation that the body starts producing human chorionic gonadotropin (hCG). This is a hormone that plays a role in many early pregnancy symptoms. Pregnancy tests check levels of this hormone.

By the time a person knows that they are pregnant, it is usually week 4 or later.

In this article, we explore what can cause dizziness in early pregnancy. We also look at how to manage and prevent dizziness.

woman experiencing dizziness in early pregnancy week 1 lying on sofa holding headShare on Pinterest
Credit Image: VioletaStoimenova/Getty Images

Several factors can cause a person to feel dizzy during pregnancy. These include:

Reduced blood pressure

Low blood pressure can occur during pregnancy, and it can cause dizziness and lightheadedness. The walls of the blood vessels relax due to the presence of pregnancy hormones. As a result, blood pressure decreases, which can make a person feel lightheaded. Blood pressure may reach its lowest point in the second trimester.

Hunger

During pregnancy, people need more calories. When a person does not eat frequently enough, their blood sugar levels can drop, causing dizziness.

Morning sickness

For some people, the nausea of morning sickness causes dizziness. And if morning sickness is severe, a person may vomit so frequently that they become malnourished or dehydrated.

Blood vessel changes

During pregnancy, the body creates more blood vessels to nourish the fetus. To do this and stay healthy, the body needs more iron and other nutrients.

Low iron levels and blood pressure can keep oxygen from reaching the brain as effectively as usual. This can result in dizziness.

Also, as the uterus expands, it can put pressure on blood vessels. This, too, can affect blood supply and lead to dizziness.

Iron deficiency anemia

During pregnancy, the body needs additional nutrients to enable the fetus to grow. People can develop iron deficiency anemia if they do not take in additional iron at this time. The condition can lead to faintness, dizziness, and fatigue, among other symptoms.

Various factors can lead to anemia, and a doctor will likely carry out tests to identify the cause.

People with vegetarian or vegan diets may be particularly prone to iron deficiency anemia during pregnancy. It is a good idea to bring this up with the healthcare team early on, because certain diets can influence a person’s need for supplements.

Standing up too quickly

People with any risk factors for dizziness during pregnancy may find that the dizziness is worse when they stand up too fast, especially just after waking.

HIgh levels of progesterone relax the smooth muscles — and therefore the blood vessel walls — during pregnancy. This makes a person more likely to feel dizzy when they stand up.

Needles

The Centers for Disease Control and Prevention (CDC) report that fainting is common after vaccination. It does not appear to be due to the contents of the vaccine, so they suggest that the process of vaccination is what triggers fainting.

Most people have blood tests early in pregnancy, and some people have needle phobia or fear the sight of their blood.

A sudden drop in blood pressure, called a vasovagal response, can result from fear. This response can cause dizziness or fainting.

If a person experiences this type of dizziness, lying down with their feet slightly raised and their body tilted slightly to the left usually resolves it.

Every pregnancy is different. There is no standard timeline for pregnancy symptoms.

The levels of hCG rise during the first trimester. As a result, many people find that their symptoms are more noticeable during the first trimester, then taper off in the second trimester.

Some common early pregnancy symptoms include:

  • breast changes, such as breast pain or swelling
  • fatigue
  • headaches
  • body aches
  • constipation
  • morning sickness, nausea, or vomiting
  • a frequent need to urinate
  • mood changes
  • food cravings
  • aversions to certain foods or smells
  • bleeding that is lighter than a period, which occurs in up to one-quarter of pregnancies
  • lower back pain, which can occur from the early stages, as the ligaments soften to prepare the body for pregnancy

May people experience feelings of warmth and reduced sensitivity to cold during pregnancy. Some research suggests that around one-third of pregnant people have hot flashes at some point, but there is no evidence that this is limited to early pregnancy.

It is possible to be pregnant and have no symptoms, just as it is possible to have many of the symptoms above and not be pregnant.

People with dizziness during pregnancy should take care to reduce the risk of falls and injuries.

These strategies may help:

  • lying on the left side when resting or sleeping
  • wearing loose clothing
  • making sure not to drive during a dizzy spell or after any known dizziness triggers

During a dizzy spell, it can help to lie down with the feet raised or sit down and put the head between the legs. This encourages blood flow to the brain.

Some strategies that may help prevent dizziness include:

  • eating small, regular meals to avoid hunger and low blood sugar
  • drinking plenty of water to prevent dehydration
  • asking a healthcare professional about ways to reduce nausea and vomiting
  • exercising moderately but regularly to promote heart health, unless a doctor advises otherwise
  • standing up slowly and holding onto something stable for support
  • avoiding sitting or standing for too long
  • taking walking or stretching breaks
  • avoiding extreme heat

During pregnancy, discuss all symptoms with a doctor or midwife at each appointment. Doing this helps them identify any problems early and recommend safe ways to ease discomfort.

Call a member of the healthcare team if any of the following occurs:

  • severe dizziness that does not go away
  • fainting or losing consciousness
  • a racing heart with dizziness
  • heavy bleeding and dizziness
  • vomiting that makes it hard to consume enough foods and drinks

Dizziness is a common pregnancy symptom, and like other early symptoms, it often goes away without medical treatment. Dizziness may return later in the pregnancy as the growing uterus puts pressure on various blood vessels.

If dizziness is severe, a doctor may recommend diagnostic tests, such as for anemia.

A person should not ignore dizziness or other symptoms during pregnancy, as these can be a warning from the body.