Headaches and dizziness in pregnancy: causes and warning signs

Headaches and dizziness are quite common in pregnancy. They are often due to everyday, harmless causes and ease with simple measures. Still, knowing what certain symptoms mean helps you tell when to relax and when to let your doctor know.

Why do headaches happen?

• Hormone changes: Especially in the first trimester, hormones can trigger headaches.
• Increased blood volume: The amount of circulating blood rises in pregnancy and the vessels adapt, which can cause temporary pain.
• Thirst and hunger: Not drinking enough or going long without food are common causes.
• Poor sleep and tiredness: Irregular sleep increases pain.
• Tension and stress: Tightness in the neck and shoulder muscles causes tension-type headaches.
• Caffeine withdrawal: Cutting caffeine suddenly causes headaches in some people.
• Eye strain and screens: Long screen time can also add to headaches.

Why does dizziness happen?

• Lower blood pressure: In pregnancy the vessels relax and blood pressure can drop, especially in the first and second trimesters. Standing up quickly can cause dizziness.
• Low blood sugar: Skipping meals can make you dizzy.
• Thirst and heat: Hot rooms and standing for a long time make it worse.
• Lying on your back: Later in pregnancy, lying on your back lets the growing womb press on large blood vessels, which can cause dizziness.
• Anaemia: Iron deficiency can cause dizziness and tiredness; it is checked with blood tests at your check-ups.

Things that may help

• Drink enough through the day; do not skip meals and have small snacks.
• Get up slowly: sit for a few seconds before standing from bed or a chair.
• With a headache, rest in a dark, quiet room and place a cool or warm compress on your forehead or neck.
• Stretch your neck and shoulders gently or have a massage.
• Sleep regularly and take screen breaks.
• When dizziness starts, sit or lie on your side right away; do not try to stay standing.
• Choose side sleeping over lying on your back.
• Ask your doctor before taking any medicine for headaches.

Why does blood pressure matter?

High blood pressure is a condition to watch in pregnancy, which is why your blood pressure is measured at every check-up. A headache that is new, does not go away or is severe, especially in the second half of pregnancy, should be assessed for blood pressure and pre-eclampsia. Most people do not get it, but spotting it early is important.

When to contact your doctor

• If a headache is severe, starts suddenly or does not go away with simple measures and rest
• If a headache comes with blurred vision, flashing lights, dark spots or double vision
• If it comes with sudden swelling of the face or hands or pain in the upper right abdomen
• If dizziness keeps recurring or you feel as if you will faint
• If a headache comes with fever, a stiff neck or sensitivity to light
• If you measure your blood pressure at home and it is above the limit your doctor gave you
• If you faint, have a seizure, trouble speaking, numbness in the face or arm, or a very sudden severe headache, call 112 (or your local emergency number) or go to the nearest emergency room

What you can do

Drinking water, eating regularly, getting up slowly and lying on your side is enough for most people. Noting your symptoms and sharing them with your doctor at the check-up reassures both of you.

This article is for information only; your doctor's or midwife's advice for your own situation always comes first.