Objective To determine the normal range of shock index (SI), blood pressure (BP), mean arterial pressure (MAP) and heart rate (HR) among postpartum women in a low‐resource setting. Methods In a prospective cohort study, vital signs were recorded 1 hour after delivery among postpartum women with normal blood loss who delivered in Abakaliki, Nigeria, from April to July 2019. Results Among 225 women, the median (95% reference range) was 120 (100–155.8), 70 (60–94), and 90 (66.5–116.6) mm Hg for systolic BP, diastolic BP, and MAP, respectively; 82 (65–102) bpm for HR; and 0.69 (0.48–0.89) for SI. The upper SI limit of 0.89 supported the current value of 0.9 as the upper limit; however, the lower SI limit of 0.48 corresponded to the current lower limit for a non‐obstetric population (0.5). The SI of more than half of the study women (n=126; 56.0%) was within the normal range for non‐obstetric women (0.5–0.7). Conclusion Although hemodynamic changes in pregnancy widen the SI range, 56.0% of women maintained SI within the non‐obstetric reference range. In low‐resource settings, the current normal obstetric SI range of 0.7–0.9 should be revised to 0.5–0.9 to accommodate this lower threshold.

Objective: To determine the normal range of shock index (SI), blood pressure (BP), mean arterial pressure (MAP) and heart rate (HR) among postpartum women and to compare shock index with the normal range in the current literature.Methods: This is a prospective cohort study evaluating vital signs collected at one hour of delivery in women with normal blood loss delivered in Abakaliki, Nigeria. Results: The median (95% reference range) was 120 (100 - 155.8) for systolic BP, 70 (60 - 94) for diastolic BP, 90 (66.5 - 116.6) for MAP, 82 (65 - 102) for HR, and 0.69 (0.48 - 0.89) for SI. The upper limit of SI of 0.89 in this study did support the current literature suggesting a threshold of 0.9 as upper limit of normal. However, the lower limit of SI of 0.48 in this study corresponds to the lower limit of 0.5 for non-obstetric population. Over half (56%) of the study cohorts maintained shock index values within the normal range (0.5 - 0.7) for non-obstetric population. Conclusion: Although haemodynamic changes of pregnancy widens the range of shock index in obstetric population, 56% of the participants maintained normal shock index within the reference range for non-obstetric population. We recommend that the normal obstetric shock index range of 0.7 - 0.9 in current literature be changed to 0.5 - 0.9 to accommodate this lower threshold.