Mycobacterium tuberculosis infection in pregnancy: A systematic review

Pregnancy may be associated with risk of developing tuberculosis (TB) in those infected with Mycobacterium tuberculosis (Mtb). The perinatal period could provide opportunities for targeted screening and treatment. This study aims to synthesise published literature on Mtb infection in pregnancy, relating to prevalence, natural history, test performance, cascade of care, and treatment. We searched Ovid MEDLINE, Embase+Embase Classic, Web of Science, and Cochrane Central Register of Controlled Trials (CENTRAL) on October 3, 2023, and 47 studies met the inclusion criteria. The prevalence of Mtb infection was as high as 57.0% in some populations, with rates increasing with maternal age and in women from high TB-incidence settings. Five studies quantified perinatal progression from Mtb infection to active TB disease, with two demonstrating increased risk compared to non-pregnant populations (IRR 1.3-1.4 during pregnancy and IRR 1.9-2 postpartum). Concordance between Tuberculin Skin Test (TST) and Interferon Gamma-Release Assay (IGRA) ranged from 49.4%-96.3%, with k-values of 0.19-0.56. High screening adherence was reported, with 62.0-100.0% completing antenatal TST and 81.0-100.0% of those positive having chest radiograph. Four studies of TB preventative treatment (TPT) did not find a significant association with serious adverse events. The antenatal period could provide opportunities for contextualised Mtb infection screening and treatment. As women with increased age and from high TB-incidence settings demonstrate higher prevalence and risk of disease, this cohort should be prioritised. TPT appears safe and feasible; however, further studies are needed to optimise algorithms, ensuring pregnant and postpartum women can make evidence-informed decisions for effective TB prevention.