Almost fainting while pregnant: what to know

Sit or lie down immediately so you do not fall. Tell your maternity care team about the episode, particularly if it recurs or you actually lose consciousness.

Pregnancy changes blood flow and can make light-headedness more noticeable after standing quickly, standing for a long time, becoming too warm or lying flat later in pregnancy. Not eating regularly or losing fluids through vomiting can also contribute.

Other possibilities include anaemia, an abnormal heart rhythm or an illness affecting blood pressure. The circumstances, accompanying symptoms and whether episodes repeat help a clinician decide what needs checking.

Stop what you are doing, sit with your head lowered or lie on your side, and loosen tight clothing. Move away from heat and ask someone to stay nearby. Once the feeling settles, rise slowly, drink water and have a suitable snack if you have not eaten.

Do not drive, climb stairs alone or remain standing while dizzy. Record what you were doing, how long the feeling lasted and whether there was pain, bleeding, breathlessness, palpitations, headache or a change in the baby's usual movements.

Seek emergency help if you faint, injure yourself, have chest pain, severe breathlessness, a racing or irregular heartbeat, one-sided weakness, confusion, a seizure, a severe headache or vision changes. Urgent maternity assessment is also needed with vaginal bleeding, severe abdominal pain, fluid leaking, or reduced baby movements compared with the usual pattern.

Contact your maternity care team promptly for repeated near-fainting, persistent dizziness, ongoing vomiting, difficulty keeping fluids down or symptoms that do not improve after resting. These features warrant assessment regardless of whether faintness is common in pregnancy.

Ask whether your blood pressure, blood count, glucose or heart rhythm should be checked. Mention all medicines and supplements, recent vomiting or diarrhoea, and any previous heart condition. Your clinician can also advise how to adapt meals, fluids and activity to your pregnancy.