Objective To present the pregnancy results and interim birth results of a pragmatic randomised controlled trial comparing routine iron prophylaxis with screening and treatment for anaemia during pregnancy in a setting of endemic malaria and HIV.

Design A pragmatic randomised controlled trial.

Setting Two health centres (1° de Maio and Machava) in Maputo, Mozambique, a setting of endemic malaria and high prevalence of HIV.

Participants Pregnant women (≥18-year-olds; non-high-risk pregnancy, n=4326) attending prenatal care consultation at the two health centres were recruited to the trial.

Interventions The women were randomly allocated to either Routine iron (n=2184; 60 mg ferrous sulfate plus 400 μg of folic acid daily throughout pregnancy) or Selective iron (n=2142; screening and treatment for anaemia and daily intake of 1 mg of folic acid).

Outcome measures The primary outcomes were preterm delivery (delivery <37 weeks of gestation) and low birth weight (<2500 g). The secondary outcomes were symptoms suggestive of malaria and self-reported malaria during pregnancy; birth length; caesarean section; maternal and child health status after delivery.

Results The number of follow-up visits was similar in the two groups. Between the first and fifth visits, the two groups were similar regarding the occurrence of fever, headache, cold/chills, nausea/vomiting and body aches. There was a suggestion of increased incidence of self-reported malaria during pregnancy (OR 1.37, 95% CI 0.98 to1.92) in the Routine iron group. Birth data were available for 1109 (51%) in the Routine iron group and for 1149 (54%) in the Selective iron group. The birth outcomes were relatively similar in the two groups. However, there was a suggestion (statistically non-significant) of poorer outcomes in the Routine iron group with regard to long hospital stay after birth (relative risk (RR) 1.43, 95% CI 0.97 to 1.26; risk difference (RD) 0.02, 95% CI −0.00 to 0.03) and unavailability of delivery data (RR 1.06, 95% CI 1.00 to 1.13; RD 0.03, 95% CI −0.01 to 0.07).

Conclusions These interim results suggest that routine iron prophylaxis during pregnancy did not confer advantage over screening and treatment for anaemia regarding maternal and child health. Complete data on birth outcomes are being collected for firmer conclusions.

Trial registration The trial is registered at ClinicalTrials.gov, number NCT00488579 (June 2007). The first women were randomised to the trial proper April 2007–March 2008. The pilot was November 2006–March 2008. The 3-month lag was due to technical difficulties in completing trial registration.