Some people who experience dizziness during the first week of being pregnant may think that pregnancy is the cause. However, early pregnancy symptoms typically appear no earlier than week 4, when a person misses their period and can get a positive pregnancy test.
Doctors calculate pregnancy from the first day of a person’s last period, rather than from conception. Therefore, although a person will come to know the dates of their official first week of pregnancy, they were not really pregnant at that point.
Even if a person defines the first week of pregnancy as the week following conception, pregnancy will still not cause dizziness.
The reason for this is that pregnancy begins with implantation 8–10 days after ovulation. Implantation occurs when the fertilized egg embeds in the uterus.
It is only after implantation that the body starts producing human chorionic gonadotropin (hCG), a hormone that plays a role in many early pregnancy symptoms. By the time a person knows that they are pregnant, they are usually in week 4 or later.
In this article, we examine what may cause dizziness in early pregnancy. We also look at how to manage and prevent dizziness.
Several factors can cause a person to feel dizzy during pregnancy. These include:
Lower blood pressure
Pregnancy hormones, including hCG, cause the blood vessels to relax. As a result, blood pressure decreases, which can make a person feel lightheaded.
During pregnancy, people need to eat more calories. When a person does not eat frequently enough, their blood sugar can drop, which causes dizziness.
For some people, the nausea of morning sickness causes dizziness. If morning sickness is severe, a person may vomit so frequently that they become malnourished or dehydrated.
Slower blood flow
During the second and third trimesters of pregnancy, the expanding uterus can put pressure on blood vessels. This pressure may slow blood flow to the heart, making a person feel dizzy.
Iron deficiency anemia
People can develop iron deficiency anemia when there is not enough iron in their body. Iron deficiency can lead to symptoms that include dizziness and fatigue.
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 after waking.
Most people have blood tests early in pregnancy, and these involve the use of needles.
Some people have a needle phobia or fear the sight of blood.
A sudden drop in blood pressure, called a vasovagal response, can occur as a result of fear. This response can cause dizziness or even fainting.
Every pregnancy is different. There is no standard timeline for pregnancy symptoms.
The levels of hCG rise during the first trimester. Due to this, many people find that their symptoms become more noticeable during the first trimester and then taper off in the second trimester.
Some common early pregnancy symptoms include:
- breast changes, such as breast pain or swelling
- light bleeding that is lighter than a period — this occurs in up to one-quarter of pregnancies
- morning sickness, nausea, or vomiting
- a frequent need to urinate
- mood changes
- food cravings
- aversions to certain foods or smells
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 who experience dizziness during pregnancy should take precautions to reduce the risk of a fall or other injuries. Doing the following may help:
- avoiding having very hot showers
- avoiding swimming alone
- refraining from driving during a dizzy spell or after any known dizziness triggers
- lying down or sitting down and putting the head between the legs to encourage 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 doctor about strategies to reduce nausea and vomiting
- exercising to promote heart health
- standing up slowly and grabbing something stable for support
- avoiding sitting or standing for too long and taking walking or stretching breaks
- avoiding extreme heat
A person needs to discuss all pregnancy symptoms with a doctor or midwife at each appointment. Doing this will help them identify any problems early and recommend safe treatments to ease pregnancy discomforts.
A person should call a healthcare professional if a pregnant individual is experiencing:
- severe dizziness that does not go away
- fainting or losing consciousness
- a racing heart with dizziness
- heavy bleeding and dizziness
Dizziness is a common pregnancy symptom. As with many first trimester symptoms, it often goes away without intervention. However, dizziness may return later in pregnancy, as the growing uterus puts pressure on various blood vessels.
If dizziness is severe, a doctor may recommend diagnostic tests, especially for anemia.
A person should not ignore dizziness or any other pregnancy symptoms, as they can be a warning from the body of potential problems.