Risk of venous thromboembolic complications in pregnant trauma patients: A matched cohort study

Trauma and pregnancy are both risk factors for venous thromboembolism (VTE). We hypothesized that pregnant blunt trauma patients would have a higher incidence of VTE complications compared with matched nonpregnant females.

We conducted a retrospective cohort study using National Trauma Data Bank data from 2017 to 2022. Female patients with blunt mechanism, age between 15 and 50 years old, were eligible for inclusion. Patients who presented as transfers, hospitalized for less than 72 h, discharged against medical advice, injury severity score <9, or abbreviated injury scale = 6 of any region were excluded. Pregnant patients were matched 1:2 with nonpregnant female patients by age, injury characteristics, comorbidities, and type and timing of chemical VTE prophylaxis. The primary outcomes were the incidences of VTE, deep vein thrombosis (DVT), and pulmonary embolism (PE). Secondary outcomes included other complications and length of stay.

We included 735 pregnant and 1470 matched nonpregnant controls. The median time to initiate chemical VTE prophylaxis was 33 h in pregnant and 34 h in nonpregnant patients (p = 0.42). The incidence of VTE in pregnant blunt trauma patients was 27 (3.7%) versus 45 (3.1%) in matched controls (p = 0.446). There were no significant differences in DVT, PE, or any other complication or mortality or in ICU or hospital length of stay. Unplanned admissions to the ICU were significantly more frequent in pregnant patients (3.8% vs. 2.2% and p = 0.026).

The incidence of VTE complications was similar in pregnant and matched nonpregnant female blunt trauma patients in this retrospective cohort study, supporting the safety of current VTE prophylaxis practices in pregnant patients.