ABO and sexually transmitted disease: Additionally, interventions aimed at reducing risk of malaria infection during pregnancy may beneficially affect the burden of STI in relation to ABO.24 25 Intermittent preventative treatment using sulfadoxine-pyrimethamine (IPTp-SP) has been shown to exhibit a dose–response protective effect against ABO, and as this effect is strongest among women with malaria and/or STI, it has been suggested to have a broad-range effect decreasing malaria parasite load and partially protect against numerous gram-positive and gram-negative bacteria.24