Eligible women were asked if they wished to join the trial and, if so, written, informed consent was obtained. An entry questionnaire was then completed and a finger-prick blood sample obtained for determination of Hb and preparation of two thick blood films. Provided the woman had a Hb >7g/dl, she was then given a study number and formally entered into the trial. Women were then individually randomised to receive SP and iron + folic acid ('early' folate group) or SP and iron ('late' folate group).