dizziness.
last revised · reviewed 2026-07-05
Feeling light-headed or dizzy is common in pregnancy, because progesterone widens your blood vessels and blood pressure naturally dips, especially in the first and second trimesters. It usually passes with sitting down, eating, and drinking — but fainting or dizziness with bleeding needs medical review.
what it feels like
A woozy, light-headed swimming feeling, often when standing up quickly, standing still for a long time, getting overheated, or going too long without food. Vision may briefly grey or sparkle at the edges. Rarely it tips into an actual faint.
why it happens
Progesterone relaxes and widens blood vessels so more blood reaches the baby — the side effect is lower blood pressure and slower return of blood to your brain when you change position. Growing blood volume takes time to catch up, and low blood sugar or anaemia can add to the effect. Later on, lying flat on your back can let the uterus compress a major vein, with the same result.
what helps
- Stand up slowly, in stages — sit first, pause, then rise
- Eat small, regular meals to keep blood sugar steady
- Drink plenty of fluids, more in warm weather
- Avoid standing still for long periods; shift your weight and move your feet
- From mid-pregnancy, lie on your side rather than flat on your back
- If you feel faint, sit and put your head between your knees, or lie on your left side until it passes
- Keep rooms ventilated and dress in layers you can shed
when to call your midwife or doctor
- You actually faint — always report a faint to your midwife or doctor
- Dizziness with vaginal bleeding or tummy pain — urgent same-day assessment
- Dizziness with palpitations, chest pain, or breathlessness at rest
- Frequent or worsening dizziness, or dizziness with a severe headache or visual changes — call your midwife or doctor
This page is general information, not a diagnosis. When in doubt, call — no midwife has ever minded a careful question.
common questions
Why do I feel dizzy in early pregnancy?
Progesterone widens your blood vessels from the first weeks, lowering blood pressure before your blood volume has fully expanded to compensate. The result is that classic light-headed wobble on standing up. It usually improves as pregnancy progresses and blood volume catches up.
Is dizziness a sign something is wrong with the baby?
On its own, no — occasional light-headedness is a normal circulatory side effect of pregnancy and doesn't affect the baby. It needs review when paired with bleeding, pain, fainting, or palpitations, so mention those to your midwife or doctor promptly.
Why shouldn't I lie flat on my back later in pregnancy?
From around mid-pregnancy the weight of the uterus can compress the large vein returning blood to your heart when you lie flat, causing dizziness and reducing blood flow. Sleeping and resting on your side — either side — avoids this, and side-sleeping is advised from 28 weeks.
read it in context
Dizziness tends to show up around these weeks of pregnancy:
related symptoms
- Headaches
Headaches are common in pregnancy, especially the first trimester, driven by hormone shifts, increased blood volume, tiredness, and often caffeine withdrawal.
- Bleeding gums
Swollen, tender gums that bleed when brushing affect the majority of pregnant women — pregnancy hormones increase blood flow to the gums and amplify their reaction to plaque.
- Constipation
Constipation affects up to 4 in 10 pregnant women, because progesterone relaxes the muscles of the gut and slows digestion right down.
know what's normal, week by week
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