Dizziness and Fainting in Pregnancy
The short answer
Dizziness is common during pregnancy, affecting many pregnant people at various stages. It can be caused by low blood pressure, blood pooling in the legs, low blood sugar, anemia, dehydration, or the growing uterus compressing major blood vessels. While usually benign, fainting should always be reported to your provider.
Parents everywhere have the same worry. You are doing the right thing by looking into it.
By Age
What to expect by age
Dizziness in early pregnancy is often caused by rapidly expanding blood vessels and hormonal changes that lower blood pressure. Standing up slowly, staying hydrated, eating small frequent meals, and avoiding prolonged standing can help. If you feel faint, sit or lie down immediately.
As the uterus grows, it can press on blood vessels, particularly when lying flat on your back. This is called supine hypotensive syndrome. Try to sleep on your left side to improve blood flow. Dizziness when standing quickly (orthostatic hypotension) is also common. Rise slowly from sitting or lying positions.
Dizziness may worsen in the third trimester as the uterus is largest and blood volume demands are highest. Avoid lying flat on your back for extended periods. If dizziness is accompanied by headache, vision changes, or swelling, report it promptly as it could be related to blood pressure issues.
What Should You Do?
When to take action
- Brief lightheadedness when standing up quickly that resolves in seconds
- Feeling dizzy in hot environments, crowded spaces, or after standing too long
- Dizziness that improves with sitting, lying down, eating, or drinking water
- Mild lightheadedness without loss of consciousness
- Frequent episodes of dizziness or near-fainting
- Dizziness is accompanied by persistent rapid heartbeat or palpitations
- You actually fainted, even if briefly
- Fainting or dizziness accompanied by vaginal bleeding, severe abdominal pain, or severe headache
- Dizziness with chest pain, severe shortness of breath, or blurred vision
- You fainted and hit your head or belly
Sources
Related Resources
Trust your instincts. If something feels wrong, reach out to your pediatrician.
Worrying about your baby means you care. That is a good thing.
Related Maternal Concerns
Low Blood Pressure in Pregnancy
Low blood pressure (hypotension) is common during pregnancy, especially in the first and second trimesters. It is caused by hormonal changes that relax blood vessel walls and the expanding circulatory system. Most low blood pressure in pregnancy is harmless, though it can cause dizziness and fainting.
Anemia During Pregnancy
Anemia during pregnancy is very common, affecting up to 40% of pregnant people worldwide. It is most often caused by iron deficiency due to the increased blood volume and iron demands of pregnancy. Symptoms include extreme fatigue, weakness, pale skin, dizziness, and shortness of breath. It is treatable with iron supplementation and dietary changes.
Dealing with Abnormal Prenatal Screening Results
An abnormal prenatal screening result can be terrifying, but it is important to understand that screening tests are designed to cast a wide net and have significant false-positive rates. Most people with abnormal screening results go on to have healthy babies after further testing confirms the baby is fine. An abnormal screening is a reason for more information, not a diagnosis.
Pregnancy Over 35 (Advanced Maternal Age)
While pregnancy after 35 carries some increased risks (including chromosomal abnormalities, gestational diabetes, and hypertension), the vast majority of people over 35 have healthy pregnancies and healthy babies. The term "geriatric pregnancy" is outdated and does not reflect reality. With appropriate prenatal care and monitoring, outcomes are excellent.
Amniocentesis Questions and Fears
Amniocentesis is a diagnostic test performed between 15-20 weeks that analyzes amniotic fluid to detect chromosomal conditions and genetic disorders with over 99% accuracy. The risk of pregnancy loss from the procedure is approximately 1 in 500-1,000 when performed by an experienced provider. Understanding the actual risks can help you make an informed decision.
20-Week Anatomy Scan Unexpected Findings
The 20-week anatomy scan checks your baby's major organs, structures, and growth. Most scans are completely normal. When unexpected findings are identified, they range from minor variants that resolve on their own to conditions that need further evaluation. Many findings require nothing more than a follow-up ultrasound to confirm the baby is developing well.