Prevalence of curable STIs and bacterial vaginosis during pregnancy in sub-Saharan Africa: a systematic review and meta-analysis

Objective STIs remain a global public health problem with a high burden among pregnant women. STIs in pregnant women may lead to various adverse pregnancy outcomes. In most sub-Saharan African countries, syndromic management is used for screening and treatment of STIs. We aimed to update and summarise pooled prevalence of curable STIs and bacterial vaginosis (BV) among pregnant women in sub-Saharan Africa. Methods Electronic databases and reference lists of relevant published and unpublished studies were searched from March 2015 to October 2020. Studies were included if they estimated prevalence of Chlamydia trachomatis (CT), Trichomonas vaginalis (TV), Neisseria gonorrhoeae (NG), Treponema pallidum (syphilis), Mycoplasma genitalium (MG) and BV among pregnant women in sub-Saharan Africa. Meta-analyses were performed with observed prevalences corrected for diagnostic errors to estimate the pooled prevalence of diagnosed infections by region. Results A total of 48 studies met the inclusion criteria, providing 85-point prevalence estimates for curable STIs and BV. Pooled prevalence estimates (with 95% CI and number of women tested) were as follows: MG: 13.5% (4.0-27.2, n=1076); CT: 10.8% (6.9-15.5, n=6700); TV: 13.8% (10.0-18.0, n=9264); NG: 3.3% (2.1-4.7, n=6019); syphilis: 2.9% (2.0-4.0, n=95 308) and BV: 36.6% (27.1-46.6, n=5042). By region, BV was the most prevalent and ranged from 28.5% (24.5-32.8, n=1030) in Eastern Africa to 52.4% (33.5-70.9, n=2305) in Southern Africa; NG had the lowest prevalence, ranging from 1.4% (95% CI 0.1 to 3.1, n=367) in Central Africa to 4.4% (95% CI 2.6 to 6.4, n=4042) in Southern Africa. Conclusion The prevalence of curable STIs and BV in sub-Saharan Africa is substantial in pregnant women but most prevalent in Southern Africa where HIV prevalence is highest. It is crucial to integrate screening of curable STIs into antenatal care programmes that have previously focused on diagnosis and treatment of syphilis and HIV.