Anaemia in Pregnancy
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Direct answer
Anaemia in pregnancy is a haemoglobin below 11 g/dL, graded in Indian practice as mild (10 to 10.9), moderate (7 to 9.9) and severe (below 7 g/dL); by national survey data roughly half or more of Indian pregnant women are anaemic, and iron deficiency dominates. Oral iron (100 to 200 mg elemental iron daily) is first-line; intravenous iron — iron sucrose or a single 1000 mg ferric carboxymaltose infusion — is chosen for intolerance, non-response or late moderate anaemia; transfusion is reserved for severe anaemia near term or around 5 g/dL with complications. Untreated, anaemia drives heart failure, infection, preterm birth and death from postpartum haemorrhage.
What you must remember
- Grading used in India: mild 10 to 10.9 g/dL, moderate 7 to 9.9 g/dL, severe below 7 g/dL — the commonest medical disorder of pregnancy in India, with physiological haemodilution peaking at 30 to 34 weeks and a total pregnancy iron requirement of about 1000 mg.
- Oral iron: 100 to 200 mg elemental iron daily with folic acid, on an empty stomach away from tea; expect about 1 g/dL haemoglobin rise in two to three weeks.
- Intravenous iron: intolerance, non-response or late-presenting moderate anaemia — iron sucrose 200 mg on alternate days, or ferric carboxymaltose 1000 mg as a single short infusion in the second or third trimester.
- Transfusion: severe anaemia with cardiac failure, haemoglobin about 5 g/dL or below, or severe anaemia near term without time for iron — packed cells given slowly with diuretic cover.
- Maternal complications: high-output cardiac failure, infection and poor tolerance of haemorrhage — postpartum haemorrhage kills anaemic mothers; fetal complications: growth restriction, preterm birth and perinatal loss.
- Prevention: programme-driven daily iron-folic acid from the second trimester, deworming, diet counselling and haemoglobin testing each trimester.
Common confusion
The examinable pair is physiological haemodilution versus true deficiency: both drop haemoglobin around 30 to 34 weeks, but a low mean corpuscular volume with low ferritin means deficiency needing treatment. The second trap is the transfusion reflex — moderate anaemia at 32 weeks responds to intravenous iron, while severe anaemia in heart failure is transfused slowly.
Exam-focused takeaway
FMGE asks numbers: the 11 g/dL threshold, the 7 g/dL severe line, the 1 g/dL rise expected in two to three weeks, and the 1000 mg ferric carboxymaltose dose. A 34-week woman at 8 g/dL intolerant of oral iron gets intravenous iron; heart failure at 5 g/dL gets slow packed cells. The anaemia-PPH death link makes this a guaranteed screening topic.
Frequently asked questions
At what haemoglobin is pregnancy anaemic?
Below 11 g/dL, with severe anaemia below 7 g/dL in Indian grading; the trough around 30 to 34 weeks is partly physiological haemodilution.
Why does haemoglobin fall in normal pregnancy?
Plasma volume expands by about 40 to 50 per cent while red cell mass rises only 20 to 30 per cent, diluting the blood — most evident at 30 to 34 weeks.
When is intravenous iron preferred over oral iron?
For intolerance, failure of haemoglobin response, malabsorption, continuing losses, or moderate anaemia presenting in the late third trimester — ferric carboxymaltose as a single large infusion, iron sucrose in divided doses.
What response is expected to oral iron?
A reticulocyte rise within one to two weeks and a haemoglobin climb of roughly 1 g/dL every two to three weeks; failure demands a search for non-compliance, blood loss or another cause.
When is transfusion indicated?
Severe anaemia with cardiac failure, haemoglobin around 5 g/dL or less, or severe anaemia near delivery without time for iron — packed cells slowly with diuretic cover.