The prevention of anaemia in pregnancy in primigravidae in the guinea savanna of Nigeria.

Two hundred Hausa primigravidae at Zaria were divided into five groups in a randomized double-blind trial of antenatal oral antimalarial prophylaxis, and haematinic supplements. Group 1 received no active treatment. Groups 2 to 5 were given chloroquine 600 mg base once, followed by proguanil 100 mg per day. In addition, group 3 received iron 60 mg daily, group 4 folic acid 1 mg daily, and group 5 iron plus folic acid. Forty-five percent were anaemic (haemoglobin (Hb) less than 11.0 g dl-1) at first attendance before 24 weeks of gestation, and malaria parasitaemia (predominantly Plasmodium falciparum) was seen in 27%, of whom 60% were anaemic. The mean Hb fell during pregnancy in group 1, and seven patients in this group had to be removed from the trial and treated for severe anaemia (packed cell volume (PCV) less than 0.26). Only five patients in the other groups developed severe anaemia (P = 0.006), two of whom had malaria following failure to take treatment. Patients in group 1 had the lowest mean Hb at 28 and 36 weeks of gestation, and patients receiving antimalarials and iron (groups 3 and 5) had the highest Hb at 28 weeks, but differences were not significant, possibly due to removal from the trial of patients with severe anaemia. Anaemia (Hb less than 12.0 g dl-1) at six weeks after delivery was observed in 61% of those not receiving active treatment (group 1), in 39% of those protected against malaria but not receiving iron supplements (groups 2 and 4) and in only 18% of patients receiving both antimalarials and iron (groups 3 and 5). Folic acid had no significant effect on mean Hb. Proguanil was confirmed to be a highly effective causal prophylaxis. Prevention of malaria, without folic acid supplements, reduced the frequency of megaloblastic erythropoiesis from 56% to 25%. Folic acid supplements abolished megaloblastosis, except in three patients who were apparently not taking the treatment prescribed. Red cell folate (RCF) concentrations were higher in subjects with malaria, probably due to intracellular synthesis by plasmodia. Infants of mothers not receiving antimalarials appeared to have an erythroid hyperplasia. Maternal folate supplements raised infants' serum folate and RCF. Fourteen per cent had low birth weight (less than 2500 g), and the perinatal death rate was 11%; the greatest number were in group 1, but not significantly. A regime is proposed for the prevention of malaria, iron deficiency, folate deficiency and anaemia in pregnancy in the guinea savanna of Nigeria.