Dosage of Sulfadoxine–Pyrimethamine and Risk of Low Birth Weight in a Cohort of Zambian Pregnant Women in a Low Malaria Prevalence Region

Abstract

Abstract. In Lusaka, Zambia, where malaria prevalence is low, national guidelines continue to recommend that all pregnant women receive sulfadoxine-pyrimethamine (SP) for malaria prophylaxis monthly at every scheduled antenatal care visit after 16 weeks of gestation. Human immunodeficiency virus (HIV)-positive women should receive co-trimoxazole prophylaxis for HIV and not SP, but many still receive SP. We sought to determine whether increased dosage of SP is still associated with a reduced risk of low birth weight (LBW) in an area where malaria transmission is low. Our secondary objective was to determine whether any association between SP and LBW is modified by receipt of antiretroviral therapy (ART). We analyzed data routinely collected from a cohort of HIV-positive pregnant women with singleton births in Lusaka, Zambia, between February 2006 and December 2012. We used a logPoisson model to estimate the risk of LBW by dosage of SP and to determine whether the association between SP and LBW varied by receipt of ART. Risk of LBW declined as the number of doses increased and appeared lowest among women who received three doses (adjusted risk ratio [ARR] = 0.78; 95% confidence interval [CI] = 0.64-0.95). In addition, women receiving combination ART had a higher risk of delivering an LBW infant compared with women receiving no treatment or prophylaxis (ARR = 1.18; 95% CI = 1.09-1.28), but this risk was attenuated among women who were receiving SP (risk ratio = 1.09; 95% CI = 0.99-1.21). SP was associated with a reduced risk of LBW in HIVpositive women, including those receiving ART, in a low malaria prevalence region.

Coverage and effectiveness of intermittent preventive treatment in pregnancy with sulfadoxine–pyrimethamine (IPTp-SP) on adverse pregnancy outcomes in the Mount Cameroon area, South West Cameroon

“…This is consistent with extensive reports on beneficial associations between the use of IPTp-SP and low birthweight still seen in areas where the efficacy of SP to clear parasitaemia has clearly decreased [11,12]. Besides its anti-malarial activity, IPTp-SP appears to confer benefit through yet undefined pathways [19,20,54]. Sulfadoxine is a broad-spectrum antibiotic that possibly exerts an inhibitory effect against non-malaria causes of LBW and preterm birth [55].…”

“…IPTp-SP appears to protect against malaria as well as other non-malarial causes of LBW such as sexually transmitted and reproductive tract infections (STIs/ RTIs). SP may exert its protection through antibacterial or anti-inflammatory actions [19,20].…”

Intermittent Preventive Treatment with Sulfadoxine–Pyrimethamine: More Than Just an Antimalarial?

“…Although administration of antiretroviral therapy (ART) to pregnant women, compared with not treating mothers, is associated with improved birthweight,15 and is clearly to the benefit of both mothers and infants, concerns remain about the safety of ART in pregnancy. As in other studies,16,17 Stoner and others found an association between ART and increased risk for low birthweight and preterm delivery 8. The reasons for this remain unclear, but may include modulation of the normal immune shift from Th1 to Th2 that occurs during pregnancy, other alterations in inflammatory cytokines, or possibly an increased risk of hypertension with resultant placental insufficiency 16.…”

Determinants of Low birthweight and Preterm Delivery in the Volta Region of Ghana: Evidence from birth records

“…This is supported by evidence from a Zambian study which reported that the bacterial and parasitic effects of SP signi cantly improved the birthweight of neonates born to women who took more doses of SP during pregnancy. The Sulphadoxine component of SP provides a broad spectrum of anti-parasitic and bacterial activities (46). Thus, constant exposure via monthly update of SP could reduce microbial density and immunological reactions leading to adverse birth outcomes such as LBW (46)(47)(48).…”