Maternal and Fetal Outcomes Associated With Scrub Typhus in Pregnancy: A Systematic Review

Abstract

Scrub typhus, caused by Orientia tsutsugamushi and transmitted by larval trombiculid mites, is endemic across much of the Asia-Pacific region. It is frequently missed or misdiagnosed in pregnant individuals, where its consequences may be severe. Despite the severe maternal and fetal risks associated with scrub typhus, a comprehensive synthesis of the infection’s total burden during pregnancy remains a critical gap in the literature. We searched five bibliographic databases (PubMed, CINAHL, MEDLINE Ultimate, ClinicalKey, and Ovid Embase), four trial registries (World Health Organization International Clinical Trials Registry Platform, ClinicalTrials.gov, the EU Clinical Trials Register, and the ISRCTN Registry), and two additional sources (Google Scholar, searched as a source of grey literature, and the One Nation One Subscription (ONOS)) platform for English-language studies published between January 1, 2015 and December 31, 2025, that reported prevalence or maternal or fetal outcomes among pregnant women with laboratory-confirmed scrub typhus. Two reviewers independently screened records, extracted data, and appraised quality using the design-appropriate Joanna Briggs Institute checklists. Eligible studies were few, small, and clinically heterogeneous; the findings were synthesized narratively in accordance with the Synthesis Without Meta-analysis guidance and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020. In total, 23 studies were eligible, reporting on 434 pregnant women with confirmed scrub typhus. A total of 18 studies were from India. Overall, 12 maternal deaths were recorded across seven studies; the largest cohort (n = 260, China) reported none. Intensive care admission ranged from 3.1% to 69.7%, and multiorgan dysfunction, hepatic and renal injury, and respiratory failure were the major maternal complications. Total fetal loss ranged from 0% to 42.4% and preterm birth from 0% to 44.4%. Earlier gestational age at infection and longer delay before treatment both predicted worse outcomes. Azithromycin was the mainstay of treatment and, in the largest cohort, was associated with improved fetal survival. All available evidence was from facility-based studies, suggesting that outcomes are driven primarily by early clinical recognition and timely initiation of appropriate treatment, and that the true community-level burden remains unknown. In endemic settings, empirical azithromycin may be considered when scrub typhus is clinically suspected, and laboratory confirmation is likely to be delayed, although this observation is based on limited, single-center data and warrants confirmation in prospective studies.