Donk, Bahar; Güllü, Deniz; Cırık, Ahmet Mirhan; Alay, Handan; Karakeçili, Faruk; Özden, Kemalettin; Can, Fatma Kesmez; Barkay, Orçun; Pshenichnaya, Natalia; Ergönül, Önder

Crimean-Congo hemorrhagic fever (CCHF) during pregnancy is associated with severe maternal and fetal complications, but evidence remains limited to heterogeneous case reports. We synthesized patient-level data from published and unpublished cases identified through systematic database searches and direct collaboration with centers in CCHF-endemic areas. We harmonized patient-level clinical, laboratory, obstetric, treatment, and outcome data for 55 pregnancies. The maternal mortality rate was 28.8% (15/52), and fetal loss occurred in 57.4% (31/54) of cases. Maternal mortality rates increased with advancing gestation, reaching 31.3% in the third trimester, but fetal loss was highest (85.7%) in the first trimester. Ribavirin treatment during the third trimester was associated with lower observed maternal mortality rates (odds ratio 0.33, 95% CI 0.13–0.84; p = 0.031). Our findings highlight gestational age–specific risks of CCHF and support the need for standardized management protocols and strengthened CCHF surveillance during pregnancy in endemic regions.