Folic acid 400 mcg daily from three months before. 4–5 mg instead if there's a previous baby with a neural tube defect, diabetes, epilepsy on medication, or obesity — that's a prescribed dose, ask.
Bloods: haemoglobin and ferritin, blood group and Rh, TSH, fasting sugar or HbA1c, HIV, HBsAg, VDRL, rubella IgG.
Rubella: if not immune, vaccinate — then avoid conceiving for one month. Rubella in early pregnancy causes deafness, heart defects and blindness, and is entirely preventable.
Thyroid: untreated hypothyroidism affects the baby's brain development. Common, cheap to test, easy to treat.
Diabetes: sugar controlled before conception. High sugar in the first weeks is when organ defects happen.
Medicines: take the whole list — including ayurvedic, homeopathic and over-the-counter — and ask which are safe. Several must be changed before, not after.
Dental check. Gum disease is linked to preterm birth.
Weight. Both ends matter. Change before conception is worth more than any effort during.
Stop smoking, alcohol, tobacco chewing, recreational drugs — both partners.
Spacing: 18–24 months between delivery and the next conception.

Mention before conceiving: consanguineous marriage, a previous child with a genetic or developmental condition, recurrent miscarriage, thalassaemia or sickle trait in either family, a child who died in infancy, deafness or blindness from birth in relatives. Any of these is a reason for genetic counselling before pregnancy, when the options are widest.

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