Dual prevalence of STIs/RTIs and malaria in pregnancy found among women in sub-Saharan Africa

A review of studies reporting estimates of the prevalence of sexually transmitted infections/reproductive tract infections (STIs/RTIs) and malaria over the past 20 years suggests that a considerable burden of malaria and STIs/RTIs exists among pregnant women attending antenatal (before birth) facilities in sub-Saharan Africa, according to a review and meta-analysis of previous studies published in the May 16 issue of JAMA, a theme issue on Global Health.

"There are 880,000 stillbirths and 1.2 million neonatal deaths each year in sub-Saharan Africa. Low birth weight (< 2.5 kg [5.5 lbs.]), attributable to intrauterine growth retardation, preterm delivery, or both, is the leading risk factor for neonatal mortality. Intrauterine infection is implicated in stillbirth and is associated with 25 percent to 40 percent of preterm births. Sexually transmitted infections and reproductive tract infections and malaria are associated with adverse birth outcomes, but both may be mitigated with preventive or presumptive treatment or by repeated screening and treatment throughout the antenatal period. The extent to which either approach may be beneficial depends on the underlying prevalence of STIs/RTIs and malaria in pregnancy," according to background information in the article.

R. Matthew Chico, M.P.H., of the London School of Hygiene and Tropical Medicine, London, and colleagues conducted a systematic review and meta-analysis to provide estimates for the dual prevalence of STIs/RTIs and malaria in pregnancy among women in sub-Saharan Africa. The researchers conducted a search for studies reporting malaria, syphilis, Neisseria gonorrhoeae, Chlamydia trachomatis, Trichomonas vaginalis, or bacterial vaginosis among pregnant women attending antenatal care facilities in sub-Saharan Africa. A total of 171 studies, which were conducted from 1990-2011, were identified that met inclusion criteria.

The studies included 340,904 women. The researchers found that the pooled prevalence estimates among studies in East and Southern Africa were: syphilis, 4.5 percent (n = 8,346 positive diagnoses), N gonorrhoeae, 3.7 percent (n = 626), C trachomatis, 6.9 percent (n = 350), T vaginalis, 29.1 percent (n = 5,502), bacterial vaginosis, 50.8 percent (n = 4,280), peripheral malaria, 32.0 percent (n = 11,688), and placental malaria, 25.8 percent (n = 1,388).

"West and Central Africa prevalence estimates were as follows: syphilis, 3.5 percent (n = 851), N gonorrhoeae, 2.7 percent (n = 73), C trachomatis, 6.1 percent (n = 357), T vaginalis, 17.8 percent (n = 822), bacterial vaginosis, 37.6 percent (n = 1,208), peripheral malaria, 38.2 percent (n = 12,242), and placental malaria, 39.9 percent (n = 4,658)," the authors write.

"The dual prevalence of malaria and STIs/RTIs is evident among pregnant women who attend antenatal facilities in sub-Saharan Africa. As malaria control and elimination efforts are brought to scale, the relative contribution of STIs/RTIs to adverse birth outcomes most likely will increase proportionately. Coinfection prevalence estimates for malaria and STIs/RTIs need to be established and routinely reported. Rigorous studies using molecular diagnostic methods are needed to characterize more accurately the prevalence of these infections and their clinical consequences. Clinical trials are needed to compare birth outcomes, operational feasibility/acceptability, and cost-effectiveness of intermittent preventive treatment during pregnancy (IPTp) with azithromycin-based combination therapy against an approach of integrated screening and treatment for malaria and STIs/RTIs," the researchers conclude.