Intermittent screening and treatment versus intermittent preventive treatment of malaria in pregnancy: a randomised controlled non-inferiority trial

Abstract

Background: The effectiveness of intermittent preventive treatment of malaria in pregnancy (IPTp) may be compromised by the spread of resistance to sulphadoxine/pyrimethamine (SP) across Africa. But little information exists on alternative drugs for IPTp or alternative strategies for the prevention of malaria in pregnancy. Therefore, we have investigated whether screening with a rapid diagnostic test and treatment of those who are positive (IST) at routine antenatal clinic attendances is as effective and as safe as SP-IPTp in pregnant women.

Methods and findings: During antenatal clinic sessions in six health facilities in Ghana held between March 2007 and September 2007, 3333 pregnant women who satisfied inclusion criteria were randomised into three intervention arms (1) standard SP-IPTp, (2) IST and treatment with SP or (3) IST and treatment with amodiaquine+artesunate (AQ+AS). All women received a long-lasting insecticide treated net. Study women had a maximum of three scheduled follow-up visits following enrollment. Haemoglobin concentration and peripheral parasitaemia were assessed between 36 and 40 weeks of gestation. Birth weight was measured at delivery or within 72 hours for babies delivered at home. Parasite prevalence at enrollment in primigravidae and in multigravidae was 29.6% and 10.2% respectively. At 36-40 weeks of gestation the prevalence of asymptomatic parasitaemia was 12.1% in study women overall and was very similar in all treatment groups. The risk of third trimester severe anaemia or low birth weight did not differ significantly between the three treatment groups regardless of gravidity. IST with AQ+AS or SP was not inferior to SP-IPTp in reducing the risk of low birth weight (RD = -1.17[95%CI; -4.39-1.02] for IST-SP vs. SP-IPTp and RD = 0.78[95%CI; -2.11-3.68] for IST-AQAS vs. SP-IPTp); third trimester severe anaemia (RD = 0.29[95%CI; -0.69-1.30] for IST-SP vs. SP-IPTp and RD = -0.36[95%CI;-1.12-0.44] for IST-AQAS vs. SP-IPTp).

Conclusion: The results of this study suggest that in an area of moderately high malaria transmission, IST with SP or AS+AQ may be a safe and effective strategy for the control of malaria in pregnancy. However, it is important that these encouraging findings are confirmed in other geographical areas and that the impact of IST on placental malaria is investigated.

Trial registration: ClinicalTrials.gov NCT00432367 [NCT00432367].

Figure 1. CONSORT chart showing enrolment and follow-up status of women in each study arm.

Figure 2. Mean change in Hb concentrations at 36 weeks gestation over baseline.

Figure 3. The effect of IST with AS + AS or SP compared with SP-IPTp on the risk of third trimester severe anaemia (panel A) or low birth weight (panel B) in women who received these interventions.

The error bars shown indicate 2-sided 95% confidence intervals (CIs). The areas bound by −5 to 5 (panel 3A) and −4 to 4 (panel 3B) indicate zone of non-inferiority. In both panels the CIs lie to the left of the upper boundaries of the CIs and include zero indicating IST is non-inferior to SP-IPTp.