What should you know about the pathophysiology of anaemia in pregnancy?

Pregnancy expands the liquid part of blood and also increases the need to make red blood cells for the pregnant person and placenta. If red-cell production does not keep pace, the blood carries less oxygen. Iron is needed to make haemoglobin, so low iron intake, limited absorption, pre-pregnancy depletion or blood loss can contribute. Other forms involve folate or vitamin B12 deficiency, inflammation, inherited blood conditions or another illness.

Anaemia may cause tiredness in pregnancy, weakness, breathlessness with activity, dizziness, headaches, palpitations, pale skin or reduced concentration. These symptoms overlap with normal pregnancy changes, so a blood count and iron-related tests help identify the pattern.

Attend recommended antenatal blood tests and tell the clinician about diet, vomiting, bleeding, previous anaemia and medicines. Treatment depends on the cause and severity. Iron therapy may be advised through an oral preparation, and another route may be considered when tablets are unsuitable or do not correct the deficiency. Do not start high-dose supplements without advice, because the cause should be confirmed.

Contact your maternity team promptly for worsening breathlessness, fainting, chest discomfort, a racing heartbeat at rest, marked weakness or bleeding. Seek emergency care for severe breathing difficulty, collapse or heavy bleeding. Keep follow-up appointments so response to treatment and the underlying cause can be checked.

Which type of anaemia do my blood results suggest? Are iron stores, folate or vitamin B12 being checked? How should I take treatment, what side effects should I expect, and when will my blood be rechecked?