Intermittent preventive treatment (or therapy) in pregnancy (IPTp) with the drug sulfadoxine-pryimethamine (SP) is a key strategy for controlling morbidity and mortality associated with malaria in both pregnant women and newborns. IPTp when given at least twice, one month apart after quickening, reduces maternal anemia, placental malaria, and low birth weight. IPTp with SP has many characteristics of a good public health intervention in that is is relatively low cost, is easy to deliver, and is generally acceptable and available. The longer half-life of SP gives it comparative advantage over alternatives.
Recently questions have arisen about the value of SP as IPT when there are increasing reports of drug resistance when tested and used in children under five years of age. Of note is a lack of study of resistance in pregnant women themselves, which always poses an ethics problem for researchers. WHO African Region issued a statement in 2005 on the efficacy of SP even under conditions of drug resistance in children under 5 and recommended continued use of SP even where resistance levels in children were up to 50%.
To support this position ter Kuile et al. concluded in the June 20th 2007 issue of JAMA that, “In areas in which 1 of 4 treatments with sulfadoxine-pyrimethamine fail in children by day 14, the 2-dose IPT with sulfadoxine-pyrimethamine regimen continues to provide substantial benefit to HIV-negative semi-immune pregnant women. However, more frequent dosing is required in HIV-positive women not using cotrimoxazole prophylaxis for opportunistic infections.” O’Meara et al. further contend that IPTp is unlikely to significantly impact the spread of SP resistant parasites.
While alternative drugs are being considered, none so far are as cheap as SP. These also require more than one dose and thus make directly observed treatment within the context of antenatal care quite difficult. More research is needed to find appropriate substitutes. Basically it is important for countries to continue using SP for IPTp for the meantime, and of course ensure that all pregnant women obtain and sleep under ITNs.